HomeMy WebLinkAboutagenda.council.worksession.20260413AGENDA
CITY COUNCIL WORK SESSION
April 13, 2026
4:00 PM, City Council Chambers
427 Rio Grande Place, Aspen
I.Work Session
I.A City Council Conversation with Planning & Zoning Commission
I.B City Council Conversation with Historic Preservation Commission
II.Council questions and comments related to items published in the most recent
information update, as needed
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CC_PZ_WS Memo_041326.pdf
CC_P&Z_WS Exhibit A 041326.pdf
Exhibit B
Chapter_26.515.___TRANSPORTATION_AND_PARKING_MANAGEMENT.pdf
Exhibit C Chapter_26.312.___NONCONFORMITIES.pdf
Exhibit D Sec._26.575.020.___Calculations_and_Measurements.pdf
CC_HPC_WS_041326.pdf
Exhibit A Transferable Development Rights Map.pdf
Exhibit B TDR Values graph 041326 .PNG
Exhibit C HP Design Guidelines Revised 05.2024_.pdf
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STAFF REPORT
TO: Aspen Mayor and City Council
FROM: Dan Folke, Planning Director
THROUGH: Ben Anderson, Community Development Director
MEETING DATE: April 13, 2026
SUBJECT: Discussion with Planning & Zoning Commission
INTENDED OUTCOME & SUMMARY:
The Planning & Zoning Commission has requested a joint work session to discuss four
topics that may require amendments to the Zoning Code. The Commission would like
to engage the City Council in a discussion about the topics summarized below and
reach consensus on directing staff to begin the policy analysis and identify potential
code amendments. Adoption of Policy Resolutions required to authorize a code
amendment will be presented to City Council for their consideration as required.
Included in this memo are the four topics, some background to frame the issue followed
by questions to start the discussion.
DISCUSSION:
1. Hierarchy of Review
There are a number of land use requests that require review and approval by
City Council, with a recommendation from the Planning & Zoning Commission.
The code also identifies requests which can be reviewed administratively by staff
with no public meeting. The Commission would like to discuss the current
hierarchy of review and identify opportunities to delegate some City Council
reviews to the Planning & Zoning Commission, and reviews that could be
administrative. The powers and duties of City Council (Chapter 26.208), the
Community Development Director (Chapter 26.210) and the Planning & Zoning
Commission (Chapter 26.212) are found in these sections and are attached as
Exhibit A. An example that requires consideration by City Council are the
temporary use of tents for more than 14 days. This is a top priority for the next
phase of the code work with Baseline Engineering during 2026.
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Q: What types of requests does City Council and Planning & Zoning Commission
believe could be delegated down the review hierarchy? What type of requests
require a public meeting?
2. Parking Mitigation
Development projects routinely have impacts to private on-site spaces and public
spaces located within right-of-way. The code currently allows parking
requirements to be met utilizing a number of tools, often in combination, including
providing onsite parking, demand management (bikeshare, carshare, transit,
pedestrian connections) or paying fees-in-lieu. In addition, neighborhoods
continue to have an increasing number of vehicles related to construction
projects, despite requiring construction management plans.
Q: Are the current mitigation strategies including Transportation Demand
Management and fees in lieu effective at addressing the impacts of parking
demand and congestion management? What else can be done to manage the
impact of construction vehicles in neighborhoods?
3. Nonconformities
Land use requests may involve properties with nonconformities (Chapter 26-312)
such as the continuation or expansion of residential uses, encroachments into
Environmentally Sensitive Areas and floor area. On occasion, conflicting criteria
are applied when multiple code sections are applicable. (such as Environmental
Sensitive Areas or Special Review) In general non-conformities are not allowed
to expand, however fully subgrade space is exempt from the calculations of net
floor area, and the footprint of subgrade space is often outside the footprint of
above grade improvements. A review of the nonconformities chapter is on the
Long Range Planning work program for 2026, City Council adopted a Policy
Resolution and staff is currently preparing amendments which are anticipated to
be presented to Planning & Zoning Commission on May 6.
Q: Does City Council want to consider changes to how non-conforming
properties are reviewed? Should subgrade space continue to be exempt from
measures of intensity and floor area?
4. Calculations and Measurements
Section 26.575.020 Calculations and Measurements of the Land Use Code is
lengthy, detailed and includes prescriptive standards for measuring floor area,
height, setbacks, and other dimensional aspects of development. The section
describes certain allowances, requirements and other prescriptions for a range of
structural components, such as porches, balconies, garages, chimneys,
mechanical equipment, projections into setbacks, etc. This code section
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determines how the development standards of each zone district are calculated
and measured. While staff realizes that this seems like an easy and obvious
pursuit, we acknowledge that this is inherently complex and potentially redefines
development rights.
Q: Does City Council want the standards reviewed for clarity, consistency and to
make them more understandable to allied professionals and the general public?
NEXT STEPS:
As discussion on the four topics is concluded, staff would like consensus to direct staff
to place the topics in the Long Range Planning work program. As mentioned the
hierarchy of review is within the scope of work for Baseline Engineering, the consultant
reviewing and preparing code amendments on a range of topics that were presented to
City Council in December 2025. Staff is also actively working on the Nonconformities
section of the code and will be bringing amendments to P&Z in May. The topics that are
not currently in the work program are Parking Mitigation and Calculations and
Measurements.
ATTACHMENTS:
Exhibit A: Powers and Duties
Exhibit B: Transportation and Parking Management
Exhibit C: Nonconformities
Exhibit D: Calculations and Measurements
CITY MANAGER NOTES:
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Exhibit A
Chapter 26.208. - CITY COUNCIL
Sec. 26.208.010. - Powers and duties.
In addition to any authority granted by state law or this Code, the City Council shall have
the following powers and duties:
(a) To initiate amendments to the text of this Title, pursuant to Chapter 26.310;
(b) To hear, review and adopt amendments to the text of this Title after recommendation by
the Commission, pursuant to Chapter 26.310;
(c) To initiate amendments to the Official Zone District Map, pursuant to Chapter 26.310;
(d) To hear, review and adopt amendments to the Official Zone District Map after
recommendation by the Planning and Zoning Commission, pursuant to Chapter 26.310;
(e) To review and approve, approve with conditions or disapprove a Planned Development
Project Review and to hear and decide appeals of a Planned Development Detailed Review
decision by the Planning and Zoning Commission or the Historic Preservation Commission,
pursuant to Chapter 26.445—Planned Development:
(f) To hear, review and designate H, Historic Overlay Districts and historic landmarks, after
recommendation from the Planning and Zoning Commission and the Historic Preservation
Commission, pursuant to Chapter 26.415;
(g) To review appeals from decisions of the Historic Preservation Commission approving,
conditionally approving or disapproving a development application for development or
demolition of an historic landmark or a development application for development or
demolition in an H, Historic Overlay District pursuant to Chapter 26.415;
(h) To adopt any plans, guidelines or documents that will be used in a guiding or regulatory
capacity by the City;
(i) To hear appeals from decisions of decision-making bodies as enabled in each Chapter of
this Title;
(j) To approve development applications and grant development allotments as required by
Chapter 26.470, Growth Management Quota System;
(k) To hear appeals from interpretations made by the Planning Director regarding the text of
this Title and the boundaries of the Official Zone District Map, pursuant to Chapter 26.306;
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(l) To hear, review and approve, approve with conditions or disapprove a plat for
subdivision, after recommendation from the Planning and Zoning Commission pursuant to
Chapter 26.480;
(m) To hear, review and approve, approve with conditions or disapprove an application for
Public Projects Review, pursuant to Chapter 26.500, and to determine if a private
development application is eligible for Public Project Review, pursuant to Section
26.500.040(d).
(n) To create a Transferable Development Right in accordance with Chapter 26.535.
(o) To take such other actions not delegated to the Planning and Zoning Commission, the
Historic Preservation Commission, the Board of Adjustment or the Director of the
Community Development Department, as the City Council may deem desirable and
necessary to implement the provisions of this Title.
Chapter 26.210. - COMMUNITY DEVELOPMENT DEPARTMENT
Sec. 26.210.020. - Director of Community Development Department.
(a) Creation and appointment. The Community Development Director shall be the agency
head of the Community Development Department and shall be appointed by and serve at
the pleasure of the City Manager.
(b) Jurisdiction, authority and duties. In addition to the jurisdiction, authority and duties
which may be conferred upon the Community Development Department Director by other
provisions of this Code, the Community Development Department Director shall have the
following jurisdiction, authority and duties:
(1) To serve as staff to the City Council, to provide such body with planning and technical
assistance and to inform such body of all facts and information available with respect to
development applications or any other matters brought before it;
(2) To serve as staff to the Planning and Zoning Commission, to provide such body with
planning and technical assistance and to inform such body of all facts and information
available with respect to development applications or any other matters brought before it;
(3) To serve as staff to the Historic Preservation Commission, to provide such body with
planning and technical assistance, to inform such body of all facts and information
available with respect to development applications or any other matters brought before it
and to inform such body regarding historic preservation items being heard by other City
boards in advance of those hearings;
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(4) To serve as staff to the Board of Adjustment and other decision-making bodies
established by this Title and to inform such bodies of all facts and information available
with respect to development applications or any other matters brought before it;
(5) To serve as staff to the Administrative Hearing Officer, to provide such officer with
planning and technical assistance and to inform such officer of all facts and information
available with respect to appeals of decisions made by an administrative official or any
other matters brought before it;
(6) To render interpretations of this Title or the boundaries of the Official Zone District Map
pursuant to Chapter 26.306;
(7) To enforce any provision of this Title or any other provision of this Code;
(8) To establish such rules of procedure necessary for the administration of the Community
Development Department Director's responsibilities;
(9) To exempt development within an H, Historic Overlay District in accordance with
Chapter 26.415;
(10) To approve minor modifications to a development order for development or demolition
within an H, Historic Overlay District in accordance with Chapter 26.415;
(11) To exempt development in an environmentally sensitive area (ESA) in accordance with
Chapter 26.435;
(12) To exempt development which is subject to special review in accordance with Chapter
26.430;
(13) To make determinations of exemptions from the growth management quota system
(GMQS), pursuant to Chapter 26.470;
(14) To approve, approve with conditions or deny development subject to GMQS
administrative approval in accordance with Chapter 26.470;
(15) To approve development subject to subdivision administrative approval in accordance
with Chapter 26.480;
(16) To approve development subject to Planned Development administrative approval in
accordance with Chapter 26.445;
(17) To undertake all general comprehensive planning responsibilities;
(18) To initiate amendments to the text of this Title or to the Official Zone District Map,
pursuant to Chapter 26.310;
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(19) To administer the land use application fee policy, to bill applicants according to said
policy, to take such actions deemed necessary in withholding development orders or
issuing stop work orders upon nonpayment of review fees and to waive any fees or portions
thereof, upon request according to said policy;
(20) To approve, approve with conditions or deny development subject to Chapter 26.520,
Accessory Dwelling Units and Carriage Houses;
(21) To extinguish a transferable development right in accordance with Chapter 26.535;
(22) To issue and extinguish Affordable Housing Certificates in accordance with Chapter
26.540; and
(23) To assist and staff all aspects of the Master Planning process in accordance with
Chapter 26.311.
(24) To approve, approve with conditions, or disapprove an application for Administrative
Public Project review, pursuant to Chapter 26.500, and to determine if a private
development application is eligible for Public Project Review, pursuant to Section
26.500.040(d).
Chapter 26.212. - PLANNING AND ZONING COMMISSION[1]
Sec. 26.212.010. - Powers and duties.
In addition to any authority granted the Planning and Zoning Commission (hereinafter
"Commission") by state law or the Municipal Code of the City of Aspen, Colorado, the
Commission shall have the following powers and duties:
(a) To initiate amendments to the text of this Title, pursuant to Chapter 26.310;
(b) To review and make recommendations of approval or disapproval of amendments to the
text of this Title, pursuant to Chapter 26.310;
(c) To initiate amendments to the Official Zone District Map, pursuant to Chapter 26.310;
(d) To review and make recommendations of approval, approval with conditions or
disapproval to the City Council in regard to amendments of the Official Zone District Map,
pursuant to Chapter 26.310;
(e) To review and make recommendations of approval, approval with conditions, or
disapproval to the City Council on a Planned Development Project Review and to approve,
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approve with conditions, or deny Planned Development Detailed Review, pursuant to
Chapter 26.445, Planned Development;
(f) To review and grant allotments for office, commercial and lodge pursuant to growth
management quota system (GMQS), pursuant to Chapter 26.470;
(g) To hear, review and recommend approval, approval with conditions or disapproval of a
plat for subdivision, pursuant to Chapter 26.480;
(h) To hear and approve, approve with conditions or disapprove conditional uses pursuant
to Chapter 26.425;
(i) To hear and approve, approve with conditions or disapprove development subject to
special review, pursuant to Chapter 26.430;
(j) To hear and approve, approve with conditions or disapprove development in
environmentally sensitive areas (ESA), pursuant to Chapter 26.435;
(k) To make its special knowledge and expertise available upon reasonable written request
and authorization of the City Council to any official, department, board, commission or
agency of the City, County, State or the federal government;
(l) To adopt such rules of procedure necessary for the administration of its responsibilities
not inconsistent with this Title;
(m) To grant variances, not including variances to allowable FAR or height, from the
provisions of this Title when a consolidated application is presented to the Commission for
review and approval pursuant to Chapter 26.314;
(n) To grant variances from the provisions of this Title when a consolidated application is
presented to the Commission for review and approval pursuant to Chapter 26.314;
(o) To hear, review and approve variances to the residential design guidelines, pursuant to
Chapter 26.410;
(p) To hear and decide appeals from and review any order, requirement, decision or
determination made by any administrative official charged with the enforcement of
Chapter 26.410, including appeals of interpretation of the text of the residential design
standards. The Commission may only grant relief from the residential design standards. A
variance from the residential design standards does not grant an approval to vary other
standards of this Chapter that may be provided by another decision-making administrative
body; and
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(q) To hear, review and approve, approve with conditions or disapprove an application for
Public Projects Review, pursuant to Chapter 26.500.
(r) To hear, review and approve, approve with conditions or disapprove an application
appealing the Community Development Director's determination that Demolition has been
triggered pursuant to Chapter 26.580.
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Exhibit B
Title 26 - LAND USE REGULATIONS
PART 500 - SUPPLEMENTARY REGULATIONS
Chapter 26.515. TRANSPORTATION AND PARKING MANAGEMENT
Aspen, Colorado, Municipal Code Created: 2026-03-27 14:30:32 [EST]
(Supp. No. 6)
Page 1 of 12
Chapter 26.515. TRANSPORTATION AND PARKING MANAGEMENT
Sec. 26.515.010. Purpose.
This Chapter establishes unified transportation and mobility standards to promote the city's policies relating
to mobility, access to employment opportunities, and sustainability. This chapter implements policies from the
Aspen Area Community Plan to:
• Limit vehicle trips into Aspen to 1993 levels, and reduce peak-hour vehicle-trips to at or below 1993
levels;
• Use Transportation Demand Management tools to accommodate additional person trips in the Aspen
Area;
• Maintain the reliability and improve the convenience of City of Aspen transit services;
• Expand and improve bicycle parking and storage within the Urban Growth Boundary;
• Improve the convenience, safety, and quality of experience for bicyclists and pedestrians on streets
and trails;
• Require development to mitigate its transportation impacts; and
• Develop a strategic parking plan that manages the supply of parking and reduces the adverse impacts
of the automobile.
This Chapter establishes a variety of ways for property owners and developers to mitigate their impacts on
the transportation network. As new development and growth occur, increased burdens on the transportation
system can make it more difficult for the City to meet its transportation and air quality goals. To the extent that
increased travel demand can shift away from automobile dependence, development and growth can be
compatible with, and even support, these goals.
To promote this shift in travel behavior, the City has transformed its approach to parking requirements to
focus on the promotion and expansion of mobility options, including more walkable development patterns and a
more efficient parking system, as well as the provision of public and development-based mobility resources. This
will directly improve the travel experience and quality of life within growth areas, while helping to maintain the
City's transportation-system and air-quality standards.
This is accomplished through a new integrated approach, which incorporates the City's Transportation
Impact Analysis (TIA) Guidelines with Off-Street Parking Requirements. Where the TIA serves to evaluate the
potential adverse effects of proposed projects on Aspen's transportation systems, the off-street parking
regulations focus on on-site mitigation needs resulting from the provision of parking.
Applicants will use a simplified, two-tiered process that:
(a) Determines the project's TIA applicability and calculates the project's resulting "parking requirement,"
and
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(b) Provides a Mobility Plan that includes the applicant's parking and mobility mitigation requirements,
which includes the provision of parking, utilization of cash-in-lieu, and/or provision mobility options,
including TIA mitigations if applicable.
The City then reviews the project's mitigations for parking and mobility together as part of the project's land use
application.
(a) Adoption of Transportation Impact Analysis (TIA) Guidelines. Pursuant to the powers and authority
conferred by the Charter of the City, there is hereby adopted and incorporated herein by reference as
fully set forth those standards contained in the City of Aspen's Transportation Impact Analysis
Guidelines, as may be amended, updated and expanded from time to time by City Council Resolution
(referred to in this Code as the "TIA Guidelines"). At least one (1) copy of the TIA Guidelines shall be
available for public inspection at the Community Development, Engineering, and Transportation
Departments.
(b) Definitions. As used in this Section, the following terms shall be defined as follows:
Mobility Measures. Specific tools, strategies, and policies approved in the Mobility Plan. These include the
Transportation Demand Management (TDM) and/or Multimodal Level of Service (MMLOS) Mitigation Tools
prescribed by the TIA, defined as follows:
• Transportation Demand Management (TDM) Tools, which are strategies and policies to reduce travel
demand, particularly by single-occupancy vehicles, and
• Multi-Modal Level of Service (MMLOS) Tools, which are improvements to transportation service
quality for travelers using a variety of modes including pedestrians, bicyclists, and transit passengers.
Mobility Plan. A complete mitigation plan for a proposed development's transportation and parking system
impacts.
Parking Maximum. The maximum number of Parking Spaces provided on-site for a designated use before
triggering compliance with Shared Parking Requirements.
Parking Minimum. The minimum number of Parking Spaces required on-site for a designated use.
Parking Requirement. The sum of a project's required Parking, as provided in Section 26.515.020(c).
Parking Space, Accessory. A Parking Space that is managed to limit access to individuals engaged with on-site
uses (residents, tenants, and their guests/customers), but are shared between all on-site land uses across
different peaks in service throughout a 24-hour/day period.
Parking Space, Guest/Loading. A Parking Space that is managed to provide 24-hour/day access to a
development for guests, deliveries and loading to the public, service providers, and other nonresident
visitors to a development on a non-permanent basis.
Parking Space, Municipal. A Parking Space that is provided within City of Aspen facilities, or directly managed
by the City of Aspen, whether located in a private or City-owned parking facility.
Parking Space, Priced. A Parking Space - whether reserved, accessory, or public - that is priced comparable to
market rates at all times of operation.
Parking Space, Public. A Parking Space that is managed to provide at least twelve (12) hours of public use in
any 24-hour/day period, with approved signage to effectively identify these hours of public access.
Parking Space, Reserved. A Parking Space that is managed to limit access to specified individuals or specific
on-site land uses.
Parking, Shared. Parking that is shared between multiple, distinct land uses, on the same site or between
proximate sites, to make more efficient use of spaces and reduce overall supply needs. Shared Parking is
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required on a development which exceeds its on-site parking provision maximum standard. Shared parking
can be used to reduce a project's Parking Requirement. Shared Parking may include off-site parking spaces
and/or priced parking spaces.
Surplus Mobility Measures. Any additional mitigation credits remaining after TIA-subject projects have met
the TIA requirements.
Transportation Impact Analysis (TIA). Technical analysis guidelines for potential transportation impacts
generated by development projects within the City of Aspen.
Sec. 26.515.020. Applicability.
This Chapter applies to all development and redevelopment which meets the definition of Demolition, or is a
Change in Use, as defined in Chapter 26.470, Growth Management Quota System.
(a) Determination of Applicability. The applicant may request a preliminary pre-application conference
with staff from the Community Development Department to determine the applicability of the
requirements of this Chapter for the proposed development. The following chart details the process for
complying with the requirements of this Section through the creation of a mobility plan. The TIA
Guidelines are available on the City of Aspen website and may be used to determine whether a project
is subject to or exempt from the TIA.
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Figure 1: Applicability chart illustrating how to create a Mobility Plan.
(b) Requirements. This Chapter requires all applicable development to submit a Mobility Plan, which
addresses the following:
• TIA applicability, and
• TIA compliance (as applicable), and
• The provision of parking, and
• Cash-in-lieu of parking (as applicable), and
• Surplus mobility measures (as applicable).
The City then reviews the project's proposed TIA and Mobility Plan together as part of the project's Land Use
Application.
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Sec. 26.515.030. Transportation Mitigation.
(a) General Requirements. All applicable development shall mitigate its projected transportation impacts as
provided in this Chapter. Refer to the Transportation Impact Analysis (TIA) for project applicability. Mobility
requirements shall be satisfied through use of the following approaches, either alone or in combination
(1) Mobility Measures. Applicable development must provide Transportation Demand Management (TDM)
and Multi-Modal Level of Service (MMLOS) measures as provided for in the Transportation Impact
Analysis (TIA) Guidelines. These measures shall be maintained for the life of the development. All
requirements shall be incorporated in the project's Development Agreement, pursuant to Chapter
26.490, Development Documents.
(2) Surplus Mobility Measures. Upon satisfaction of TIA requirements, a development's Mobility Plan may
include surplus mobility measures, where credit is provided over the minimum TIA requirements and
applied towards Parking Requirements outlined in Table 26.515-1. The proportion of surplus mobility
measures permitted for a development is outlined in Table 26.515-2.
Sec. 26.515.040. Parking Requirements.
(a) General requirements. All applicable development shall accommodate its projected parking impacts as
provided in this Chapter. Parking Requirements shall be satisfied through use of the following either alone or
in combination.
(1) Parking Requirement Calculation. Parking Requirements shall be calculated for each use within a
development according to Table 26.515-1.
(2) Parking Provision Minimum. Applicable development shall satisfy the minimum Parking Provision
Requirement, as calculated in Table 26.515-1. Minimum parking provisions may be reduced in
combination with mobility measures and transportation system impact fees in accordance with the
standards in Table 26.515-2.
(3) Parking Provision Maximum. To create appropriate site planning and provision of parking, applicable
development shall not provide on-site parking in excess of one hundred twenty-five percent (125%) of
the Parking Provision Maximum requirement in the form of Reserved Parking Spaces or Accessory
Parking Spaces, unless the total number of on-site spaces in excess of one hundred twenty-five percent
(125%) of the Parking Provision Maximum are provided as Public Parking Spaces.
Table 26.515-1 Parking Impact Requirement Calculations
Use Aspen Infill Area All Other AreasParking
Requirement (in units) Parking
Requirement
(in units)
Parking
Maximum
(in units)
Commercial(1) 1 unit / 1,000 sf
Net Leasable
Space
1.25 units /
1,000 SF NLA
3 units per 1,000 sf NLA(2)
Residential -
Single-Family and Duplex(4)
Lesser of 1 unit
per bedroom or
2 units per
Dwelling Unit
Greater of 1.25
units per
bedroom or 2.5
units per
dwelling unit
Lesser of 1 unit per bedroom or 2
per unit
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Residential -
Accessory Dwelling Units and
Carriage Houses(3) (4)
1 unit per unit 1.25 units per
unit
1 unit per unit(3)
Residential -
Multi-Family (as a single use)
1 unit per
Dwelling Unit
1.25 units per
dwelling unit
Lesser of 1 unit per bedroom or
two units per Dwelling Unit
Residential -
Multi-Family within a mixed-use
building
1 unit per
Dwelling Unit
1.25 units per
dwelling unit
1 per Dwelling Unit(2)
Hotel/Lodge 0.5 units per
Key
0.7 units per
Key
0.7 units per Key(2)
All Other Uses (civic, cultural,
public uses, essential public
facilities, child care centers, etc.)
Established by
Special Review
according to the
review criteria
of Section
26.515.080.
N/A Established by Special Review
according to the review criteria of
Section 26.515.080.
Key to Table 26.515-1:
•(1) = Up to one hundred percent (100%) of Parking Requirement, may be provided through cash-in-lieu.
•(2) = A reduction in Parking Requirement may be approved, pursuant to Chapter 26.430, Special review and
according to the review criteria of Section 26.515.080
•(3) = A reduction in Parking Requirements may be approved, pursuant to Chapter 26.520, Accessory dwelling
units and carriage houses.
•(4) = All Single-Family and Duplex dwelling units, as well as ADUs and Carriage Houses shall provide their
Parking Requirement as off-street, on-site parking spaces.
• SF = Square feet
• NLA = Net leasable square feet of commercial space
(b) Fractional Requirement Computed. When any calculation of Parking Requirements results in a fractional unit,
that fractional unit may be paid through a cash-in-lieu payment or satisfied through one (1) whole additional
on-site parking or mobility commitment credit.
Sec. 26.515.050. Meeting Parking Requirements.
(a) General requirements. Parking Requirements shall be satisfied through the following provisions alone or in
combination and described in a project's Mobility Plan:
(1) Cash-in-lieu. Cash-in-lieu payments may be made to satisfy Parking Requirements as outlined by zone
district in Table 26.515-2, and according to Section 26.515.090.
(2) Provision of Off-Street Parking.
a. On-Site Parking. Off-street parking may be provided on-site in applicable zone districts to satisfy
Parking Requirements, with Reserved and Accessory spaces not to exceed the Parking Maximums
outlined below in Table 26.515-1. Shared parking may be counted provided that a Shared Parking
Agreement and a shared-parking analysis, as approved by the Community Development Director,
is executed.
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b. Off-Site Parking. Off-street parking may be provided off-site in applicable zone districts to satisfy
Parking Requirements, provided that a Shared Parking Agreement and a shared-parking analysis,
as approved by the Community Development Director, is executed. Off-site parking is subject to
Special Review per Chapter 26.430 and Section 26.515.080.
c. Reserved and Accessory Spaces. For both On-Site Parking and Off-Site Parking, Reserved and
Accessory spaces in excess of the Parking Provision Maximums outlined below in Table 26.515-1
are subject to the Shared Parking standards in Section 26.515.040(a)(3).
(3) Shared Parking Spaces. For both On-Site Parking and Off-Site parking, shared parking spaces may be
provided contingent upon a shared parking analysis being completed and a Shared Parking Agreement
being executed, as approved by the Community Development Director.
(4) Mobility Measures. Mobility Measures, as defined in Section 26.515.010(b), may be provided, as
follows:
a. Where projects are TIA exempt, Mobility Measures may be provided to satisfy Parking
Requirements as outlined by zone district in Table 26.515-2.
b. Where projects are subject to the TIA, Surplus Mobility Measures (after the minimum TIA
mitigation requirements have been met) may be provided to satisfy Parking Requirements as
outlined by zone district in Table 26.515-2.
The extent to which a project may satisfy its Parking Requirements with Mobility Commitments, On-Site Parking
provision, and Cash-in-Lieu will vary by location, according to Table 26.515-2 below.
Table 26.515-2 - Parking Requirements by Zone District
Location Options for Meeting Parking Requirements
Additional TIA
Credits (Projects
Subject to TIA)
Mobility
Commitments
(Projects
Exempt from
TIA)
On-Site Parking
Provision
Cash-In-Lieu of
Parking Fee
Payment
Commercial Core (CC) and
Commercial-1 (C-1) zones
Up to 2
Additional TIA
Credits
Up to 2 Mobility
Commitments
* Up to 20% of
the
Requirement.
Up to 100% of
the
requirement if
subgrade.
Up to 100% of
the
Requirement
Remaining Commercial, Lodging,
and Lodging Overlay Zones
1 Additional TIA
Credit (equal to
1 Parking Unit)
1 Mobility
Commitment
(equal to 1
Parking Unit)
At least 60%
and up to 100%
of the
Requirement
Up to 40% of
the
Requirement
Remaining Infill Area 1 Additional TIA
Credit (equal to
1 Parking Unit)
1 Mobility
Commitment
(equal to 1
Parking Unit)
Up to 100% of
the
Requirement
Up to 100% of
the
Requirement
All other Areas 1 Additional TIA
Credit (equal to
1 Parking Unit)
1 Mobility
Commitment
(equal to 1
Parking Unit)
At least 60%
and up to 100%
of the
Requirement
Up to 40% of
the
Requirement
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Parking Requirements are subject to the following standards:
(1) If the Parking Requirement is subject to establishment by adoption of a Planned Development final
development plan, review is subject to Chapter 26.445, Planned Development.
(2) If the Parking Requirement is established through a special review, the standards and procedures of
Section 26.515.080, Special Review Standards apply.
(3) If the Parking Requirement is met via cash-in-lieu, the standards and procedures set forth at Section
26.515.090, Cash-in-Lieu of Parking apply.
(4) For properties listed on the Aspen Inventory of Historic Landmark Sites and Structures, a waiver of the
Parking Requirement may be approved, pursuant to Chapter 26.430, Special Review, and according to
the review criteria set forth below.
(5) For lodging projects with flexible unit configurations, also known as "lock-off units," each separate
"key," or rentable division, shall constitute a unit for the purposes of this Section.
(6) The Parking Requirement for projects with multiple, distinct land uses (residential, commercial,
lodging, or other) may be lowered, if the applicant submits a shared-parking analysis, approved by the
Community Development Director, which results in a peak-parking-demand measure that is less than
the Parking Requirement established by Table 26.515-1. The application for a shared parking analysis
shall be reviewed by The Transportation, Parking, Engineering, and Community Development
Departments and approved by the Planning and Zoning Commission as a Special Review (Section
26.430).
(7) *Off-street parking provision on a parcel that abuts an Aspen Pedestrian Mall may only be provided in
an on-site, subgrade parking structure. Alternatively, parcels abutting an Aspen Pedestrian Mall may
provide all Parking Requirements through the payment of Cash-in-Lieu (Section 26.515.090).
Sec. 26.515.060. Procedures for Review.
Development and redevelopment applications shall be reviewed pursuant to the following procedures, as
well as standards and the Common Development Review Procedures set forth in Chapter 26.304.
(a) Review Authority. All applications will be reviewed administratively for compliance with this Chapter
and relevant guidelines in conjunction with a project's land use application, unless otherwise specified.
In all circumstances, the final land use review body shall approve the TIA, after considering a
recommendation from the Engineering, Transportation, and Community Development Departments.
(b) Review Process. For all applicable development, Mobility Plan review is completed in conjunction with
required land use reviews. Pursuant to Section 26.304.020, Pre-application Conference, applicants are
encouraged, although not required, to meet with a member of the Community Development
Department to clarify requirements of this Section and to determine applicability.
(1) For development only subject to administrative-level land use reviews, or for development
meeting a threshold established in the TIA Guidelines but not subject to a land use review, the
City Engineering and Transportation Departments may, on behalf of the City of Aspen, determine
that the project meets or exceeds the requirements set forth in this Chapter and the
Transportation Impact Analysis Guidelines.
When development meets an established threshold, but does not require a land use review,
review for compliance with this Chapter and the Guidelines shall be completed as part of the
building permit application.
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(2) In all circumstances, the final land use review body shall approve the TIA, after considering a
recommendation from the Engineering and Transportation Departments.
(c) Review Criteria. All applicable projects are required to submit a Mobility Plan, which shall include and
describe a project's mitigations for TIA and Parking Requirements. The Engineering, Transportation,
and Community Development Department staff shall determine whether the project conforms to this
Chapter requirements using the following standards:
(1) Project TIA and the resulting mitigation program meets requirements for exempt, minor, or major
project categories as outlined in the TIA Guidelines.
(2) Project provides full mitigation for the Parking Requirements pursuant to Section 26.515.050.
(3) If existing development is expanded, additional Parking Requirements shall be provided for that
increment of the expansion.
(4) If existing development is redeveloped, on-site parking deficits may not be maintained unless all
parking, or at least twenty (20) spaces are provided as Public Parking.
Projects failing to meet the requirements of this Section may apply for a variation to the Planning and Zoning
Commission through the Special Review process (Section 26.430 and Section 26.515.080).
Sec. 26.515.070. Off-Street Parking Requirements.
(a) Applicability. Where off-street parking spaces are provided as part of a Mobility Plan, the regulations in
Sections 26.515.070(b)—(i) apply.
(b) General. Each off-street parking space shall consist of an open area measuring eight and one half (8½) feet
wide by eighteen (18) feet long and seven (7) feet high with a maximum longitudinal slope of twelve percent
(12%) and a maximum cross slope of five percent (5%). For developments providing more than fifteen (15)
on-site parking spaces, twenty-five percent (25%) of the on-site spaces may be provided as Compact Parking
in accordance with the requirements of the Engineering Design Standards. Each parking space, except those
provided for detached residential dwellings and duplex dwellings, shall have an unobstructed access to a
street or alley. Off-street parking provided for multi-family dwellings which do not share a common parking
area may be exempted from the unobstructed access requirement subject to special review pursuant to
Chapter 26.430, Special review and the standards set forth at Section 26.515.040, Special review standards,
below.
Off-street parking must be paved with all-weather surfacing or be covered with gravel. For residential
development, a grass ring or grass-paver-type surface may be used. All parking shall be maintained in a usable
condition at all times. All development or redevelopment must be in conformance with, or bring existing parking
into conformance with, Engineering Design Standards, including but not limited to the access requirements
outlined in Chapter 4 Transportation Design.
(c) Use of off-street parking. Parking spaces shall be used for the parking of vehicles and shall not be used for
non-auto related uses such as storage units or trash containers. No off-street parking area shall be used for
the sale, repair, dismantling or servicing of any vehicles, equipment, materials or supplies, nor shall any such
activity adjacent to off-street parking spaces obstruct required access to off-street parking areas.
(d) Location of off-street parking. Off-street parking, except shared parking, publicly accessible parking, or off-
site parking as approved as part of a mobility plan, shall be located on the same parcel as the principal use or
an adjacent parcel under the same ownership as the lot occupied by the principal use. For all uses, parking
shall be accessed from an alley or secondary road where one exists unless otherwise established according to
this Chapter.
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(e) Detached and duplex residential dwelling parking. Off-street parking provided for detached residential
dwellings and duplex dwellings is not required to have unobstructed access to a street or alley, but shall not
block access of emergency apparatus to the property or to structures located on the property. This allows for
"stacking" of vehicles where a vehicle is parked directly behind another.
(f) State Highway 82 off-street parking. All parking required for uses fronting State Highway 82 shall be accessed
from the alley, if an alley exists, and shall not enter from or exit onto State Highway 82.
(g) Surface parking. Surface parking is prohibited or requires conditional use review as a principal use of a lot or
parcel in some Zone Districts (See Chapter 26.710). Where surface parking is permitted and eight (8) or more
spaces are provided, the parking area shall include one (1) tree with a planter area of twenty (20) square feet
for each four (4) parking spaces. Planter areas may be combined but shall be proximate to the parking
spaces. The Planning and Zoning Commission may waive or modify this requirement on a per case basis.
Parking within structures is exempt from this landscaping provision.
(h) Restrictions on drainage, grading and traffic impact. Off-street parking spaces shall be graded to ensure
drainage does not create any flooding or water quality impacts and shall be provided with entrances and
exits so as to minimize traffic congestion and traffic hazards.
(i) Restrictions on lighting. Lighting facilities for off-street parking spaces, if provided, shall be arranged and
shielded so that lights neither unreasonably disturb occupants of adjacent residential dwellings nor interfere
with driver vision. All outdoor lighting shall comply with the outdoor lighting regulations, Section 26.575.150.
Sec. 26.515.080. Special Review Standards.
Whenever the transportation, mobility, and parking impacts of a proposed development are subject to
special review, an application shall be processed as a special review in accordance with the common development
review procedures set forth in Chapter 26.304 and be evaluated according to the following standards. Review is by
the Planning and Zoning Commission.
If the project requires review by the Historic Preservation Commission and the Community Development
Director has authorized consolidation pursuant to Subsection 26.304.060(b), the Historic Preservation Commission
shall approve, approve with conditions or disapprove the special review application.
A special review for establishing, varying or waiving transportation, mobility, or off-street parking
requirements may be approved, approved with conditions or denied based on its conformance with all of the
following criteria:
(1) The transportation, mobility, and off-street parking needs of the residents, customers, guests and
employees of the project have been met, taking into account potential uses of the parcel, the
projected traffic generation of the project, any shared parking opportunities, expected schedule of
parking demands, the projected impacts on the on-street parking of the neighborhood, the proximity
to mass transit routes and the downtown area and any special services, such as vans, provided for
residents, guests and employees.
(2) An on-site mitigation solution meeting the requirements and guidelines is practically difficult or results
in an undesirable development scenario.
(3) Existing or planned on-site or off-site facilities adequately serve the needs of the development,
including the availability of street parking.
(a) Commercial Parking Facilities. Special Review is required for a commercial parking facility. A special review to
permit a commercial parking facility may be approved, approved with conditions or denied based on
conformance with its adherence to Commercial Design Standards and the policy goal of provision of publicly-
accessible parking in areas with high public parking demand (in order to reduce vehicle congestion and
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emissions due to vehicles circling for parking) is not offset by the proposed commercial parking facility's
potential adverse impacts of the City's multi-modal transportation system. For properties in zone districts
where Conditional Use Review is required for a Commercial Parking Facility, Conditional Use and Special
Review shall be combined.
Sec. 26.515.090. Cash-in-lieu Requirements.
(a) General. The City conducted a parking facility analysis in the fall of 2016 and determined the costs associated
with developing new parking facilities to serve the demands of development. While not all potential facilities
represented the same potential expenditure, facilities considered likely to be developed by the City required
an expected thirty-eight thousand dollars ($38,000.00) per space to develop in 2016 dollars.
(b) Cash-in-lieu. Mobility improvements serving commercial and mixed-use development are a public amenity
and serves the mobility needs of the general population. As such, the mobility needs of the general
population can be improved through various means other than the provision of on-site parking spaces,
including cash-in-lieu. A cash-in-lieu payment, for those types of development authorized to provide parking
via cash-in-lieu, may be accepted by the Community Development Director to satisfy the Parking
Requirement, as described in Section 26.515.040, above.
(1) Time of payment. The payment-in-lieu of parking shall be due and payable at the time of issuance of a
building permit. All funds shall be collected by the Community Development Director and transferred
to the Finance Director for deposit in a separate interest-bearing account.
(2) Use of funds. Monies in the account shall be used solely for the construction of a public parking facility,
transportation and mobility improvements, including vehicles or station improvements, transportation
demand management facilities or programs, shared automobiles or programs and similar
transportation or mobility-related facilities or programs as determined appropriate by the City.
(3) Refunds. Fees collected pursuant to this Section may be returned to the then-present owner of the
property for which a fee was paid, including any interest earned, if the fees have not been spent within
seven (7) years from the date fees were paid, unless the Council shall have earmarked the funds for
expenditure on a specific project, in which case the time period shall be extended by up to three (3)
more years. To obtain a refund, the present owner must submit a petition to the Finance Director
within one (1) year following the end of the seventh (7th ) year from the date payment was received by
the City.
For the purpose of this Section, payments collected shall be deemed spent on the basis of "the first
payment in shall be the first payment out." Any payment made for a project for which a building permit
is revoked or cancelled, prior to construction, may be refunded if a petition for refund is submitted to
the Finance Director within three (3) months of the date of the revocation or cancellation of the
building permit. All petitions shall be accompanied by a notarized, sworn statement that the petitioner
is the current owner of the property and that the development shall not commence without full
compliance with this Chapter and by a copy of the dated receipt issued for payment of the fee.
(4) Periodic review of rate. To ensure that the payment-in-lieu rate is fair and represents current cost
levels, it shall be reviewed every two (2) years. Any necessary amendments to this Section shall be
initiated pursuant to Section 26.310.020, Procedure for amendment.
Sec. 26.515.100. Amendments.
Amendments to an approved Mobility and Parking Requirement review by the Community Development
Director in coordination with the Engineering and Transportation Departments as needed.
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(a) Amendments to Trip Reduction Measures. Off-site MMLOS infrastructure measures that have been
implemented may not be amended at any time. Off-site MMLOS infrastructure measures that have not
been implemented, and any on-site TDM and MMLOS measures, may be amended as outlined below.
Changes shall be reviewed by the Engineering, Transportation, and Community Development
Departments to ensure the proposed change is appropriate given the site's context.
(1) Insubstantial Amendment. Any amendment to TDM or MMLOS measures resulting in the same or
more number of trips mitigated as the original approval may be approved administratively by the
Community Development Department, after considering a recommendation from the
Engineering and Transportation Departments. A land use application is required, pursuant to
Chapter 26.304, Common Development Review Procedures. The applicant shall demonstrate how
the new measure(s) is appropriate given current site conditions.
(2) Substantial Amendment. Any amendment to TDM or MMLOS measures that reduces the number
of trips mitigated shall be reviewed by City Council, after considering a recommendation from the
Community Development, Engineering, and Transportation Departments. A land use application
is required, pursuant to Chapter 26.304, Common Development Review Procedures, and the
review shall be conducted in a duly noticed public hearing, pursuant to Section 26.304.060(e),
Public Notice. City Council shall find the following standards are met:
a. The proposed change responds to changed site conditions or circumstances, including but
not limited to changes to land uses, site topography, or site plan.
b. The proposed changes will not adversely impact the immediate vicinity.
c. The proposed change meets the original intent of the approved measures.
d. The proposed changes have been approved by the Community Development Director.
Sec. 26.515.110. Appeals.
An applicant may challenge a determination made by the City in their enforcement of the requirements of
this Chapter by filing with the Community Development Director a written notice of appeal as provided in Section
26.316.030, Appeals procedures, with a full statement of the grounds for appeal. Appeals shall be reviewed by City
Council, pursuant to Chapter 26.316, Appeals.
(Ord. No. 17-2005, § 1; Ord. No. 32, 2016, § 1; Ord. No. 23, 2017, § 23; Ord. No. 13-2019)
22
Exhibit C
Title 26 - LAND USE REGULATIONS
PART 300 - GENERAL PROCEDURES AND REGULATIONS
Chapter 26.312. NONCONFORMITIES
Aspen, Colorado, Municipal Code Created: 2026-03-27 14:30:18 [EST]
(Supp. No. 6)
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Chapter 26.312. NONCONFORMITIES
Sec. 26.312.010. Purpose.
Within the Zone Districts established by this Title, there exist uses of land, buildings and structures that were
lawfully established before this Title was adopted or amended which would be in violation of the terms and
requirements of this Title. The purpose of this Chapter is to regulate and limit the continued existence of those
uses, buildings and structures that do not conform to the provisions of this Title as amended.
It is the intent of this Chapter to permit nonconformities to continue, but not to allow nonconformities to be
enlarged or expanded. The provisions of this Chapter are designed to curtail substantial investment in
nonconformities in order to preserve the integrity of the zone districts and the other provisions of this Title but
should not be construed as an abatement provision.
Sec. 26.312.020. Nonconforming uses.
(a) Authority to continue. Nonconforming uses of land or structures may continue in accordance with the
provisions of this Chapter and this Section.
(b) Normal maintenance. Normal maintenance may be performed upon nonconforming uses of land and
structures, provided that the maintenance performed within any twelve (12) consecutive month period does
not exceed ten percent (10%) of the current replacement cost of the structure.
(c) Extensions/expansions. Nonconforming uses shall not be extended or expanded. This prohibition shall be
construed so as to prevent:
(1) Enlargement of nonconforming use by increasing the net leasable area, the net livable area of a
dwelling unit, or the area within a structure in which such nonconforming use is located; or
(2) Occupancy of additional lands; or,
(3) Increasing the size, considering all dimensions, of a structure in which a nonconforming use is located.
(d) Relocation. A structure housing a nonconforming use may not be moved to another location on or off the
parcel of land on which it is located, unless the use thereafter shall conform to the limitations of the zone
district into which it is moved.
(e) Change in use. A nonconforming use shall not be changed to any other use unless the new use conforms to
the provisions of the zone district in which it is located.
(f) Abandonment or discontinuance. The intent of the owner notwithstanding, where a nonconforming use of
land or nonconforming use of structure is discontinued or abandoned for twelve (12) consecutive months,
then such use may not be reestablished or resumed, and any subsequent use must conform to the provisions
of this Title. Any nonconforming use not associated with a structure may not be restored after a
discontinuance period of more than thirty (30) days.
(g) Demolition or destruction.
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(1) Ability to restore. Any nonconforming use located in a structure which is purposefully demolished,
pursuant to the definition of Demolition, may not be continued or restored. Any nonconforming use
located in a structure undergoing construction, which does not constitute a demolition, has an
approved development order, and an approved building permit shall not be considered discontinued.
(2) Nonwillful destruction. Any nonconforming use which is demolished or destroyed by an act of nature or
through any manner not purposefully accomplished by the owner may be restored as of right,
regardless of the extent of demolition or destruction, if a building permit for reconstruction is
submitted within twenty-four (24) months of the date of demolition or destruction.
(Ord. No. 55-2000, § § 2, 3; Ord. No. 12, 2007, § § 15, 16; Ord. No. 7, 2014, § 13; Ord. No. 13-2022, § 4, 6-28-2022)
Sec. 26.312.030. Non-conforming structures.
(a) Authority to continue. A nonconforming structure devoted to a use permitted in the zone district in which it
is located may be continued in accordance with the provisions of this Chapter.
(b) Normal maintenance. Normal maintenance to nonconforming structures may be performed without
affecting the authorization to continue as a nonconforming structure.
(c) Extensions. A nonconforming structure shall not be extended by an enlargement or expansion that increases
the nonconformity. A nonconforming structure may be extended or altered in a manner that does not
change or that decreases the nonconformity.
(1) Historic structures. The first exception to this requirement shall be for a structure listed on the Aspen
Inventory of Historic Landmark Sites and Structures. Such structures may be extended into front yard,
side yard and rear yard setbacks, may be extended into the minimum distance between buildings on a
lot and may be enlarged, provided, however, such enlargement does not exceed the allowable floor
area of the existing structure by more than five hundred (500) square feet, complies with all other
requirements of this Title and receives development review approval as required by Chapter 26.415.
(2) Mandatory occupancy accessory dwelling units and carriage houses. The second exception to this
requirement shall be for a property with a detached Accessory Dwelling Unit or Carriage House
("ADU") having a mandatory occupancy requirement. Such a detached ADU may be enlarged or
expanded by up to five hundred (500) square feet of floor area, provided that this bonus floor area
shall go entirely to the detached ADU and also provided that the ADU does not exceed the maximum
size allowed for an ADU or carriage house. The enlargement or expansion must comply with all other
requirements of this Title and shall receive development review approval as required herein.
a. Procedure. The procedure for increasing the maximum floor area of a property for the purpose of
increasing the size of an ADU requires the submission of a development application. The
development application shall be processed under Chapter 26.430, Special Review.
b. Review Standards. An application for increasing the floor area of a property for the purpose of
increasing the size of an ADU shall meet the standards in Section 26.520.050, Design Standards,
unless otherwise approved pursuant to Section 26.520.080, Special Review, as well as the
following additional review standards:
1. Newly established floor area may increase the ADU up to a cumulative maximum of five
hundred (500) square feet of floor area and is required to be mitigated by either of the
following two (2) options.
(i) Extinguishment of Historic Transferable Development Right Certificates
("certificate" or "certificates"). A property owner may increase the ADU by
extinguishment of a maximum of two (2) certificates with a transfer ratio of
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two hundred fifty (250) square feet of floor area per each certificate. Refer to
Chapter 26.535 for the procedures for extinguishing certificates.
(ii) Extinguishment of unused floor area from another property. A property owner
may increase the maximum floor area of a property for the purpose of
increasing the size of an ADU by extinguishment of a maximum of five hundred
(500) square feet of available un-built floor area from one (1) property to the
ADU.
2. The additional floor area is a conversion of existing square footage which was not
previously counted in floor area. (Example: storage space made habitable or the additional
floor area creates a more desirable, livable unit with minimal additional impacts to the bulk
and mass of the ADU structure.
3. The additional floor area creates a unit which is more suitable for caretaker families.
4. The increased impacts from the larger size are outweighed by the benefits of having a
larger, more desirable ADU.
5. The area and bulk of the ADU structure, after the addition of the bonus floor area, must be
compatible with surrounding uses and the surrounding neighborhood.
6. For the transfer of allowable floor area through the use of Historic Transferable
Development Right Certificates, the certificates shall be extinguished pursuant to Chapter
26.535, Transferable Development Rights.
7. For the transfer of allowable floor area from a non-historically designated property to an
ADU deed-restricted as a mandatory occupancy unit, the applicant shall record an
instrument in a form acceptable to the City Attorney removing floor area from the sending
property to the mandatory occupancy ADU.
(d) Relocation. A nonconforming structure shall not be moved unless it thereafter conforms to the standards
and requirements of the zone district in which it is located.
(e) Unsafe structure. Any portion of a nonconforming structure which becomes physically unsafe or unlawful
due to lack of repairs and maintenance and which is declared unsafe or unlawful by a duly authorized City
official, but which an owner wishes to restore, repair or rebuild shall only be restored, repaired or rebuilt in
conformity with the provisions of this Title.
(f) Ability to restore.
(1) Non-purposeful destruction. Any nonconforming structure that is Demolished, or portion thereof which
is destroyed by an act of nature or through any manner not purposefully accomplished by the owner,
may be restored as of right if a building permit for reconstruction is submitted within twenty-four (24)
months of the date of Demolition or destruction.
(2) Purposeful destruction. Any nonconforming structure that is purposefully Demolished or portion
thereof which is purposefully destroyed, may be replaced with a different structure only if the
replacement structure is in conformance with the current provisions of this Title or unless replacement
of the nonconformity is approved pursuant to the provisions of Chapter 26.430, Special Review. Any
structure which is nonconforming in regards to the permitted density of the underlying zone district
may maintain that specific nonconformity only if a building permit for the replacement structure is
submitted within twelve (12) months of the date of demolition or destruction.
a. Density replacement. A duplex or two (2) single-family residences on a substandard parcel in a
zone district permitting such use is a nonconforming structure and subject to nonconforming
structure replacement provisions. Density on a substandard parcel is permitted to be maintained
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but the structure must comply with the dimensional requirements of the Code including single-
family floor area requirements.
(Ord. No. 1-2002, § 6 [part]; Ord. No. 9-2002, § 5; Ord. No. 35-2004, § 1; Ord. No. 7-2008; Ord. No. 13-2022, § 4, 6-
28-2022)
Sec. 26.312.040. Nonconforming accessory uses and accessory structures.
No nonconforming accessory use or accessory structure shall continue after the principal structure or use
shall have terminated unless such structure or use thereafter shall conform to the provisions of the zone district in
which it is located.
Sec. 26.312.050. Nonconforming lots of record.
(a) General. A detached single-family dwelling and customary accessory buildings may be developed on a lot of
record if:
(1) The lot of record is in separate ownership and not contiguous to lots in the same ownership; and
(2) The proposed single-family dwelling can be located on the lot so that the yard, height, open space and
floor area dimensional requirements of the zone district can be met or a variance is obtained from said
dimensional requirements pursuant to Chapter 26.314.
(b) Undivided lot. If two (2) or more lots or combinations of lots with continuous frontage in single ownership
(including husband and wife as in all cases a single owner) are of record as of November 22, 1971, regardless
of time of acquisition and if all or parts of the lots do not meet the requirements established for lot width
and area, the lots shall be considered an undivided parcel and no portion shall be used or occupied which
does meet the width and area requirements of this Title.
(c) Historic property. A lot of record containing a property listed on the Aspen Inventory of Historic Landmark
Sites and Structures need not meet the minimum lot area requirement of its zone district to allow the uses
that are permitted and conditional uses in the district subject to the standards and procedures established in
Chapter 26.415.
(Ord. No. 1-2002 § 6 [part])
Sec. 26.312.060. Lot reduction.
(a) No lot or interest therein shall be transferred, conveyed, sold or subdivided so as to create a new
nonconforming lot, to avoid, circumvent or subvert any provision of this Title or to leave remaining any lot in
violation of the dimensional requirements of this Title.
(b) No lot or portion of a lot required as a building site under this Title shall be used as a portion of a lot required
as a site for another structure.
(c) No building permit shall be issued for any lot or parcel of land which has been conveyed, sold or subdivided
in violation of this Section.
Sec. 26.312.070. Affordable housing.
Any existing nonconforming structure or use that consists of one hundred (100) percent affordable housing
that has a current or proposed APCHA deed restriction shall be exempt from the provisions of this Chapter,
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provided the one hundred (100) percent affordable housing use will be added or remain on the parcel. The
addition or existence of another land use type shall require compliance with this Chapter.
(Ord. No. 13-2022, § 4, 6-28-2022)
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Exhibit D
Sec. 26.575.020. Calculations and Measurements.
(a) Purpose. This Section sets forth methods for measuring floor area, height, setbacks, and other dimensional
aspects of development and describes certain allowances, requirements and other prescriptions for a range
of structural components, such as porches, balconies, garages, chimneys, mechanical equipment, projections
into setbacks, etc. The definitions of the terms are set forth at Section 26.104.100—Definitions.
(b) Limitations. The prescribed allowances and limitations, such as height, setbacks etc., of distinct structural
components shall not be aggregated or combined in a manner that supersedes the dimensional limitations of
an individual structural component. For example, if a deck is permitted to be developed within five (5) feet of
a property boundary and a garage must be a minimum of ten (10) feet from the same property boundary, a
garage with a deck on top of it may not be developed any closer than ten (10) feet from the property
boundary or otherwise produce an aggregated structural component that extends beyond the setback limit
of a garage.
Non-conforming aspects of a property or structure are limited to the specific physical nature of the non-
conformity. For example, a one-story structure which extends into the setback may not be developed with a
second-story addition unless the second story complies with the required setback.
Specific non-conforming aspects of a property cannot be converted or exchanged in a manner that creates or
extends a different specific non-conforming aspect of a property. For example, a property that exceeds the
allowable floor area and contains deck area that exceeds the amount which may be exempted from floor area
cannot convert deck space into additional interior space.
(c) Measuring Net Lot Area. A property's development rights are derived from Net Lot Area. This is a number
that accounts for the presence of steep slopes, easements, areas under water, and similar features of a
property. The method for calculating a parcel's Net Lot Area is as follows:
Table 26.575.020-1 Percent of parcel to be
included in Net Lot Area
to determine allowable
Floor Area
Percent of parcel to be
included in Net Lot Area
to determine allowable
Density
Areas of a parcel with 0% to 20% slope. Notes 2, 3. 100% 100%
Areas of a parcel with more than 20% and up to 30%
slope. Notes 2, 3.
For properties in the R-
15B Zone: 100%
For all other properties:
50%.
100%
Areas of a parcel with more than 30% slope. Notes 2,
3.
For properties in the R-
15B Zone: 100%
For all other properties:
0%.
100%
Areas below the high water line of a river or natural
body of water. Note 1.
0% 0%
Areas dedicated to the City or County for open space
or a public trail.
100% 100%
Areas within an existing, dedicated, reserved for
dedication, proposed for dedication by the
application, or vacated public vehicular right-of-way,
0% 0%
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public vehicular easement, or vehicular emergency
access easement. Notes 4, 5, 6.
Areas within an existing, dedicated, reserved for
dedication, or proposed for dedication by the
application private vehicular right-of-way or vehicular
easement. Notes 4, 5, 6.
0% 0%
Areas within a vacated private vehicular right-of-way
or vehicular easement, when any affected parcel has
no other established physical and legal means of
accessing a public way. Notes 4, 5, 6.
0% 0%
Areas within a vacated private vehicular right-of-way
or vehicular easement, when all affected parcels have
established alternate physical and legal means of
accessing a public way. Notes 4, 5, 6.
100% 100%
Areas of a property subject to above ground or below
ground surface easements such as utilities or an
irrigation ditch that do not coincide with vehicular
easements.
100% 100%
Notes for Table 26.575.020 - 1:
1. Lot Area shall not be reduced due to the presence of man-made water courses or features such as ditches
or ponds.
2. In instances where the natural grade of a property has been affected by prior development activity, the
Community Development Director may accept an estimation of pre-development topography prepared by a
registered land surveyor or civil engineer. The Director may require additional historical documentation,
technical studies, reports, or other information to verify a pre-development topography.
3. The total reduction in Floor Area attributable to a property's slopes shall not exceed 25%.
4. Areas of a property within a shared driveway easement, when both properties sharing the easement abut a
public right-of-way, shall not be deducted from Lot Area. This enables adjacent property owners to combine
two driveways into one without reducing development rights.
5. When a property of 9,000 square feet or less contains a private vehicular access easement dedicated to no
more than one back parcel, when such back parcel has no other means of access, the area of the access
easement shall not be deducted from Lot Area for either Floor Area or density purposes. Otherwise, areas of a
vehicular access easement serving another parcel shall be deducted from Lot Area as provided in the table
above.
6. Within the Lodge zone district, the areas located within a vacated vehicular right-of-way, a vacated public
vehicular easement, or vacated vehicular emergency access easement, if the area was vacated prior to the
adoption of Ordinance No. 11, Series of 1975, shall not be deducted from Lot Area for either Floor Area or
density purposes. Otherwise, areas within a vacated vehicular right-of-way, a vacated public vehicular
easement, or vacated vehicular emergency access easement shall be deducted from Lot Area as provided in the
table above.
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Figure 1: Shared Driveway Easement
(d) Measuring Floor Area. In measuring Floor Areas (Inclusive of Gross, Allowable, Mitigation, and Floor Area
Ratio (FAR), the following applies:
(1) General. Floor area shall be attributed to the lot or parcel upon which it is developed. In measuring a
building for the purposes of calculating Floor Areas, there shall be included all areas within the
surrounding exterior walls of the building. When measuring from the exterior walls, the measurement
shall be taken from the exterior face of framing, exterior face of structural block, exterior face of straw
bale, or similar exterior surface of the nominal structure excluding sheathing, vapor barrier,
weatherproofing membrane, exterior-mounted insulation systems, and excluding all exterior veneer
and surface treatments such as stone, stucco, bricks, shingles, clapboards or other similar exterior
veneer treatments. (Also, see setbacks.)
Note: In measuring Floor Area for the purposes of calculating employee generation and affordable
housing mitigation for single-family, duplex, and multi-family development, a distinct calculation is
made for Mitigation Floor Area. Please refer to Section 26.575.020(d)(2) below to determine which
Floor Area exclusions shall be deducted from the Gross Floor area to determine the Mitigation Area
total.
Measuring Allowable Floor Area shall include the following exclusions and exemptions included in
Section 26.575.020(d)(3)—(15).
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Figure 2: Measuring to Face of Framing
(2) Floor Area Definitions and Purpose.
a. Floor area. A general term used to describe the sum total of the gross horizontal areas of each
story of the building measured from the exterior walls of the building. Floor Area is distinct from
the specific definitions below, but may include Gross Floor Area, Mitigation Floor Area, Allowable
Floor Area. See specific definitions of each type below for additional clarity.
i. Floor Area, Gross. Gross floor area is the total horizontal area of all floors in a building, and
of all floors in any accessory structure on the same lot, measured from the exterior face
framing of the exterior walls (See Section 26.575.020(d)), or the centerline of a common
wall separating two (2) buildings, but excluding unenclosed balconies. This floor area
measurement is the total floor area in which Mitigation Floor area and Allowable floor area
exclusions are deducted from as established in Section 26.575.020(d). None of the Floor
Area Exemptions in Section 26.575.020(d) are considered in this calculation.
Gross Floor Area should be calculated and documented in any land use or building permit
application.
ii. Floor Area, Allowable. The total amount of floor area allowed on a property based on the
limitations and allowances in the applicable zone district in Title 700 and calculated
pursuant to Section 26.575.020(d), Calculations and Measurements. All exemptions and
methodology outlined in Section 26.575.020(d)(3)—(16) apply to this calculation.
iii. Floor Area, Mitigation—The Gross Floor Area of a structure minus exclusions included in
Section 26.575.020(d). This floor area measurement is used to assess required affordable
housing mitigation for a given project. For the determination of Mitigation Floor Area, a
number of the calculation methodologies listed in Section 26.575.020(d)(3)—(16), below,
are not taken. The following table lists the code sections that are not applied to the
calculation of Mitigation Floor Area. These areas are counted in their entirety in the
Mitigation Floor Area.
Specific Building Elements Does the section apply to the calculation of Mitigation Floor
Area?
Garages and carports
(Section 26.575.020(d)(8))
NO, the exemption is not taken and the entire area is
included in the calculation
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Subgrade areas (Section
26.575.020(d)(9))
NO, the exemption is not taken and the entire area is
included in the calculation
iv. Floor Area, Non-unit space. The area, considering all inclusions and exclusions as calculated
herein, within a lodge, hotel or mixed use building that is commonly shared. (Also see
Calculations and Measurements Section 26.575.020(d)(15)).
v. Floor area ratio (FAR). The total floor area of all structures on a lot divided by the lot area.
(3) Vertical circulation. When calculating vertical circulation, the circulation element shall be counted as
follows:
a. For stairs and elevators, the area of the feature shall be projected down and counted on the
lower of the two (2) levels connected by the element and not counted as Floor Area on the top-
most interior floor served by the element.
b. When a stairway or elevator connects multiple levels, the area of the feature shall be counted on
all levels as if it were a solid floor except that the area of the feature shall not be counted as Floor
Area on the top-most interior level served by the element.
c. Mechanical and overrun areas above the top-most stop of an elevator shall not be counted as
Floor Area. Areas below the lowest stop of an elevator shall not be counted as Floor Area.
(4) Attic Space and Crawl Space. Unfinished and uninhabitable space between the ceiling joists and roof
rafters of a structure or between the ground and floor framing which is accessible only as a matter of
necessity is exempt from the calculation of Floor Area as described below. Drop ceilings are not
included in the height measurement for crawl spaces.
a. Crawl spaces that meet the following are exempt from Floor Area calculations:
i. Six (6) feet or less in height measured between the hard floor structure and floor framing;
and
ii. Accessible only through an interior floor hatch, exterior access panel, or similar feature;
and
iii. Are the minimum height and size reasonably necessary for the mechanical equipment.
1. Stacked crawl spaces do not qualify for the Floor Area exemption. Crawl spaces
greater than 6 feet in height count toward Floor Area in accordance with
Section 26.575.020(d)(9), Subgrade Areas.
2. Attic space that is conveniently accessible and is either habitable or can be
made habitable shall be counted in the calculation of Floor Area.
3. Areas of an attic level with thirty (30) vertical inches or less between the
finished floor level and the finished ceiling shall be exempt, regardless of how
that space is accessed or used.
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Figure 3: Thirty inch height exemption
4. If any portion of the attic or crawl space of a structure is to be counted, then
the entire room shall be included in the calculation of Floor Area.
5. Examples of attic and crawl spaces that do and do not count toward Floor Area:
a. An attic area created above a "hung" or "false" ceiling is exempt.
b. A crawl space that is six (6) feet in height that is accessible only through
an interior hatch counts.
c. An attic area accessible only through an interior pull-down access ladder
is exempt.
d. An unfinished attic space or an unfinished crawl space over four (4) feet
in height which has convenient access is counted.
e. A crawl space that is six (6) feet in height, is accessible only through an
interior hatch and is a reasonable size to accommodate the mechanical
equipment is exempt.
(5) Decks, Balconies, Loggias, Gazebos, Trellis, Exterior Stairways, and non-Street-facing porches.
a. The calculation of the Floor Area of a building or a portion thereof shall not include decks,
balconies, trellis, exterior stairways, non-Street facing porches, gazebos and similar features,
unless the area of these features is greater than fifteen (15) percent of the allowable floor area
for the property and the use and density proposed, or as otherwise exempted by this Section.
b. If the area of these features exceeds fifteen (15) percent of the property's allowable Floor Area
(for that use and density proposed) only the areas in excess of the fifteen (15) percent shall be
attributed towards the allowable Floor Area for the property. The allowable Floor Area for the
purpose of this calculation refers to the Floor Area calculation based on the Net Lot Area, as
defined in this Chapter or as prescribed by a site-specific approval, with the following exceptions:
Floor Area bonus, or established or extinguished Transferrable Development Right certificates
are not included.
c. Decks, balconies, exterior stairways, trellis, and similar features of a mixed use, commercial, or
lodge building located within the Commercial Core (CC) Zone District, Mixed Use (MU) Zone
District, the Commercial (C-1) Zone District, the Neighborhood Commercial (NC) Zone District, the
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Lodge (L) Zone District, or the Commercial Lodge (CL) Zone District shall be exempt from Floor
Area calculations.
d. For free-market residential units located within the Mixed Use (MU) Zone District, Commercial
Core (CC) Zone District, and Commercial (C-1) Zone District, at-grade patios, decks (other than
roof-top decks), balconies, exterior stairways, trellis, and other similar features may only be
expanded up to fifteen (15) percent of the total free-market residential floor area. Such free-
market units shall not be able to utilize any other exemptions to floor area outlined in Section
26.575.020(d).
e. The area of the following features count toward deck calculation: railing, permanently fixed
seating, permanently fixed grills, and similar permanently fixed features. Permanent planter
boxes and green roofs that are a minimum of thirty (30) inches in height above or below the deck
surface, measured from the deck surface to the bottom of the planter box or green roof surface,
and that are permanently built into the structure of the roof or deck are not included in the deck
calculation. Permanent planter boxes and green roofs that do not meet the minimum
requirement count toward deck calculation.
f. Unenclosed areas beneath decks, balconies, and exterior stairways shall be exempt from Floor
Area calculations unless that area is used as a carport. (See provisions for garages and carports,
subsection (8).) Enclosed and unconditioned areas beneath porches, gazebos, and decks or
balconies when those elements have a finished floor level within thirty (30) inches of the
surrounding finished grade shall be exempt from Floor Area calculations regardless of how that
area is used.
(6) Front Porches. Porches on Street-facing façade(s) of a structure developed within thirty (30) inches of
the finished ground level shall not be counted towards allowable Floor Area. Otherwise, these
elements shall be attributed to Floor Area as a Deck.
(7) Patios. Patios developed at or within six (6) inches of finished grade shall not be counted towards Floor
Area. These features may be covered by roof overhangs or similar architectural projections of up to
four (4) feet, as measured from the face of the building, and remain exempt from Floor Area
calculations. When roof overhangs or similar architectural projections exceed four (4) feet, the entire
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feature counts toward Floor Area. Railing, permanently fixed seating, permanently fixed grills, and
similar permanently fixed features located on patios shall count toward deck calculation.
(8) Garages and carports. For all multi-family buildings, parcels containing more than two (2) residential
units, and residential units located within a mixed-use building, two hundred fifty (250) square feet of
the garage or carport area shall be excluded from the calculation of floor area per residence on the
parcel. All garage and carport area in excess of two hundred fifty (250) square feet per residence shall
be attributed towards Floor Area and Floor Area Ratio with no exclusion. Garage and carport areas for
properties containing no residential units shall be attributed towards Floor Area and Floor Area Ratio
with no exclusion.
In the R-15B Zone District, garage and carport areas shall be excluded from the calculation of Floor
Area up to a maximum exemption of five-hundred-square-foot total for the parcel.
In zone districts other than the R-15B Zone District, properties containing solely a Single-Family, two (2)
single-family residences, or a Duplex, the garage and carport area shall be excluded from the
calculation of Floor Area as follows:
Table 26.575.020-2
Size of Garage or
Carport
Area excluded per primary dwelling unit (not including Accessory Dwelling Units or
Carriage Houses)
First 0 to 250
square feet
100% of the area
Next 251 to 500
square feet
50% of the area
Areas above 500
square feet
No area excluded.
For any property abutting an alley or private road entering at the rear or side of the property, the
garage or carport area shall only be excluded from floor area calculations as described above if the
garage or carport is accessed from said alley or road. If an alley or private road does exist and is not
utilized for garage or carport access, the garage or carport area shall be attributed towards Floor Area
calculations with no exclusion. If an alley or private road does not abut the property, the garage or
carport area shall be excluded from floor area calculations as described above.
(9) Subgrade areas. Subgrade or partially subgrade levels of a structure are included in the calculation of
Floor Area based on the portion of the level exposed above grade.
The percentage of the gross area of a partially subgrade level to be counted as Floor Area shall be the
surface area of the exterior walls exposed above natural or finished grade, whichever is lower, divided
by the total exterior wall area of that level. Subgrade stories with no exposed exterior surface wall area
shall be excluded from floor area calculations.
Example: If the walls of a two thousand (2,000) square foot level are forty (40) percent exposed above
the lower of natural or finished grade then forty (40) percent of that level, eight hundred (800) square
feet is counted as Floor Area.
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Figure 4: Determining the amount of a subgrade floor to be counted as Floor Area
For the purposes of this Section, the exterior wall area to be measured shall be the interior wall area projected
outward and shall not include exterior wall areas adjacent to foundation or floors of the structure. Floor structure
does not include drop ceilings.
Figure 5: Measuring the Area of a Subgrade Wall
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Figure 6: Determining different building levels
When considering multi-level subgrade spaces, adjacent interior spaces shall be considered on the same story if
the vertical separation between the ceilings of the spaces is less than fifty (50) percent of the distance between the
floor and ceiling of either space.
When a partially subgrade space also contains a vaulted ceiling within a pitched roof, the wall area shall include
the area within the gable of the roof.
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Figure 7: Pitched Roof with subgrade calculation
For garages that are part of a subgrade area, the garage exemption is taken from the total gross below-grade area
prior to calculating the subgrade exemption. For example, a two thousand (2,000) square foot story containing a
three hundred fifty (350) square foot garage which is forty (40) percent above grade, the calculation shall be as
follows:
Garage exemption: The first two hundred fifty (250) square feet is exempt and the next one hundred (100) square
feet counts fifty (50) percent or fifty (50) square feet = three hundred (300) square feet of the garage which is
exempt.
Subgrade exemption: Two thousand (2,000) gross square feet minus three hundred (300) square feet of exempt
garage space = one thousand seven hundred (1,700) gross square feet multiplied by forty (40) percent = six
hundred eighty (680) square feet of that level which counts towards allowable Floor Area.
For subgrade spaces with adjoining crawl spaces exempt pursuant to Section 26.575.020(d)(3), a line is drawn to
separate the basement space from the crawl space for the purposes of calculating the perimeter and gross area
measurements. Exempt crawl space is not included in the perimeter, wall area, and floor area measurements.
Single-family and duplex structures shall contain no more than one (1) floor level below finished grade. A
basement with a stepped floor is allowed. The finished floor level shall be no more than fifteen (15) feet below
finished grade. A crawl space below the basement, compliant with the limitations of Section 26.575.020(d)(3), shall
be exempt from this depth limitation.
When it is necessary to determine the floor area of an individual unit within a duplex or multi-family building, it
shall be calculated from the exterior walls to the centerline of any party walls it shares with other units.
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In order to determine the subgrade area of an individual unit in a duplex or multi-family building that applies
toward Floor Area calculations, the subgrade gross square footage of an individual unit shall be multiplied by the
percentage of exterior walls exposed above grade for the entire structure.
Example:
a. The subgrade exemption for the structure is forty (40) percent (exposed wall divided by total
wall).
b. Unit A has five hundred (500) square feet below grade, measured from exterior wall to the
centerline of the party walls it shares with Unit B. Unit B has nine hundred (900) square feet.
c. 0.40 (entire duplex exposed percentage) × 500 (Unit A subgrade gross square footage) = 200
square feet subgrade floor area that applies toward the total Floor Area for Unit A. 0.40 (entire
duplex exposed percentage) × 900 (Unit B subgrade gross square footage) = 360 square feet
subgrade floor area that applies toward the Floor Area for Unit B.
(10) Accessory Dwelling Units and Carriage Houses. An accessory dwelling unit or carriage house shall be
calculated and attributed to the allowable floor area for a parcel with the same inclusions and
exclusions for calculating floor area as defined in this Section.
(11) Permanently Affordable Accessory Dwelling Units and Carriage Houses. One hundred (100) percent of
the area of an Accessory Dwelling Unit or Carriage House which is detached from the primary residence
and deed-restricted as a "for sale" affordable housing unit and transferred to a qualified purchaser in
accordance with the Aspen/Pitkin County Housing Authority Guidelines, as amended, shall be excluded
from the calculation of floor area, up to a maximum exemption of one thousand two hundred (1,200)
square feet per parcel.
In addition, the allowable floor area of a parcel containing such a permanently affordable Accessory
Dwelling Unit or Carriage House shall be increased in an amount equal to fifty (50) percent of the floor
area of the Accessory Dwelling Unit or Carriage House, up to a maximum bonus of six hundred (600)
square feet per parcel.
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(12) Sheds, Storage Areas, and similar Accessory Structures. Sheds, storage areas, greenhouses, and similar
uninhabitable accessory structures, not within a garage, are exempt from floor area limitations up to a
maximum exemption of thirty-two (32) square feet per residence. Storage areas within a garage shall
be treated as garage space eligible for the garage exemption only. Accessory structures thirty-six (36)
inches or less in height, as measured from finished grade, shall be exempt from Floor Area calculations
(also see setback limitations). Accessory structures that are both larger than thirty-two (32) square feet
per primary residence and more than thirty-six (36) inches in height shall be included in their entirety
in the calculation of Floor Area. Properties which do not contain residential units are not eligible for
this Floor Area exemption.
(13) Historic Sheds and Outbuildings. The Community Development Director may provide a parcel
containing an uninhabitable and limited function historic shed, outbuilding, or similar historic artifact
with a Floor Area exemption to accommodate the preservation of the historic resource. The shed or
outbuilding must be considered a contributing historic resource of the property. Functional
outbuildings, such as garages, art studios, home offices, and the like shall not be eligible for an
exemption. The Director may consult the Historic Preservation Commission prior to making a
determination. The Director may require the property's potential to receive Floor Area bonuses be
reduced to account for the structure. The exemption shall be by issuance of a recordable
administrative determination and shall be revocable if the artifact is removed from the property.
(14) Wildlife-Resistant Trash and Recycling Enclosures. Wildlife-resistant trash and recycling enclosures
located in residential zone districts are exempt from floor area requirements of the zone district
regulations if the enclosure is the minimum reasonably necessary to enclose the trash receptacles in
both height and footprint, is an unconditioned space not located inside other structures on the
property, and serves no other purpose such as storage, garage space, or other purposes unrelated to
protecting wildlife. Wildlife-resistant dumpster enclosures located in commercial, mixed-use, or
lodging zone districts are not exempt from floor area requirements and shall comply with zone district
requirements for Utility/Trash/Recycle areas.
Enclosures shall be located adjacent to the alley if an alley borders the property and shall not be
located in a public right-of-way. Unless otherwise approved by the Historic Preservation Commission,
enclosures shall not abut or be attached to an historic structure. Enclosures may abut other non-
historic structures.
(15) Allocation of Non-Unit Space in a mixed-use building. In order to determine the total floor area of
individual uses in a mixed-use building, the floor area for non-unit space, which is common to all uses
on the property, shall be allocated on a proportionate basis to the use categories outlined in the
subject zone district's FAR schedule. To determine the non-unit space allocation in a building, a
calculation of the building's Gross Floor Area is required. The building's Gross Floor Area, minus all non-
unit space, shall be divided proportionately amongst the individual use categories in a building. These
numbers shall then be calculated as a percent of the Gross Floor Area number.
Garages, including subgrade garages, and carports in mixed use buildings that contain residential units
are considered non-unit space.
When a feature is used exclusively by one (1) use, the space shall be attributed to the floor area for
that use.
Gross floor area calculation:
For instance, if a building was comprised of the following square footages:
2,000 sq. ft. commercial floor area (including 500 sq. ft. basement)
+ 4,000 sq. ft. free-market residential floor area
+ 2,000 sq. ft. affordable housing floor area
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+ 1,000 sq. ft. nonunit floor area (1,250 sq. ft.- 250 sq. ft. for exempt garage)
= 9,000 sq. ft. gross floor area
Percentage of use category per building floor area:
Then the total unit floor area in the building, not including non-unit space, would be eight thousand
(8,000) square feet floor area (9,000 - 1,000). Using the allocation of non-unit space standard, the uses
account for the following percentages of the total unit floor area:
Commercial floor area = 25% [(2,000/8,000) × 100]
Free-market residential floor area = 50% [(4,000/8,000) × 100]
Affordable housing floor area = 25% [(2,000/8,000) × 100]
Application of use percentages to non-unit floor area:
A proportionate share of the non-unit floor area shall then be allocated towards each use category.
Floor area exemptions that apply to non-unit space, for example a garage or top level of a shared
stairway tower, are deducted from the total non-unit floor area before allocating to each use category.
Subgrade levels that do not count toward floor area shall not be included in the use category total
when calculating floor area. This provision shall apply to all zone districts permitting mixed-use
buildings.
Therefore, the one thousand (1,000) square feet of non-unit space is allocated to the different uses as
follows:
Commercial floor area = 25% × 1,000 sq. ft. = 250 sq. ft.
Free-market residential floor area = 50% × 1,000 sq. ft. = 500 sq. ft.
Affordable housing floor area = 25% × 1,000 sq. ft. = 250 sq. ft.
The floor area for each use is as follows:
Commercial floor area: 1,500 sq. ft. (2,000 sq. ft. total minus 500 sq. ft. exempt basement) + 250
sq. ft. = 1,750 sq. ft.
Free market residential floor area: 4,000 sq. ft. + 500 sq. ft. = 4,500 sq. ft.
Affordable housing floor area: 2,000 sq. ft. + 250 sq. ft. = 2,250 sq. ft.
Examples:
1. Circulation features, for example hallways, that are shared (used by multiple uses) are considered
non-unit space.
2. A shared elevator that serves all levels of a mixed use building (even if the top level terminates
within a residential unit) is considered non-unit space.
3. Circulation that is specific to a use, for example a private elevator that only serves the residential
component (i.e. it does NOT provide access to commercial levels), is allocated to the floor area of
the specific use and is not considered non-unit space.
4. A stairway that is interior to a single unit, which for example connects a two-level commercial
space, counts toward commercial floor area.
(16) Airlocks. Permanently installed interior airlock spaces are exempt from the calculation of Floor Area
Ratio and allowable Floor Area up to a maximum exemption of one hundred (100) square feet per
building. This exemption only applies to buildings containing non-residential uses and does not apply to
single-family, duplex, or multi-family buildings.
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(e) Measuring Setbacks.
(1) General. Required setbacks shall be unoccupied and unobstructed within an area extending
horizontally from the parcel boundary to the setback line and vertically above and below grade,
excepting allowed projections as described below.
a. For new construction, and for redevelopment projects following a Demolition of a structure for
any use type, required setbacks shall be measured perpendicularly from all points of the parcel
boundary to the outermost exterior of a structure, including all exterior veneer such as brick,
stone, or other exterior treatments, but excluding allowed projections as further described in
subsection (e)(5), below. (See Figure 8.a)
Figure 8.a: Setback Measurement
(New Construction)
b. For existing single-family, duplex, and multi-family residential structures, that propose energy
efficiency or fire protection upgrades on the exterior of the structure, required setbacks shall be
measured perpendicular from all points of the parcel boundary to the exterior face of framing of
a structure, to a maximum of eight (8) inches of all exterior veneer such as brick, stone or other
exterior treatments, including fire proofing, exterior insulation, and any methods of attachment
for insulation systems, but excluding allowed projections as further described in Section
26.575.020(e)(5), below. In any instance where the addition of exterior improvements results in a
setback of five (5) feet or less, the Community Development Director shall evaluate site context
to ensure the improvements are appropriate and compliant with building codes. (See Figure 8.b)
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Figure 8.b: Setback Measurement
(Existing Structures)
c. For existing single-family, duplex and multi-family residential structures that encroach into the
setback and propose energy efficiency of fire protection upgrades on the exterior of the
structure, a maximum of eight (8) inches of all exterior veneer such as brick, stone or other
exterior treatments, including fire proofing, exterior insulation, and any methods of attachment
for insulation, may be added to the wall assembly without being considered a nonconformity and
triggering compliance with Chapter 26.430, Nonconformities. In any instance where the addition
of exterior improvements result in a setback of five (5) feet or less, the Community Development
Director shall evaluate site context to ensure the improvements are appropriate and compliant
with building codes.
(2) Determining Front, Rear, and Side Yards. The front yard setback shall be measured from the front lot
line. The Front Lot Line shall be the parcel boundary closest to or dividing a lot from a Street or street
right-of-way. All parcels have a front lot line. There shall not be more than one (1) front lot line.
The rear yard setback shall be measured from the rear lot line. The Rear Lot Line shall be the parcel
boundary opposite the front lot line. All parcels have a rear lot line. A parcel shall have only one (1) rear
lot line.
Side yard setbacks shall be measured from the side lot lines. Side lot lines shall be those parcel
boundaries other than a front or rear lot line. All parcels will have at least one (1) side lot line and may
have multiple side lot lines.
For corner parcels, the front lot line shall be the parcel boundary along the Street with the longest
block length and the remaining boundary shall be a side lot line.
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For corner parcels where the parcel boundary follows a curving Street, the midpoint of the curve shall be used to
differentiate the front lot line and the side lot line. In this case, the boundary segment with the shortest Street
frontage shall be the front lot line.
Figure 10: Corner lot with curved street
For reverse curve lots, the curved portion of the lot line shall be considered the front lot line and the two (2)
opposing parcel boundaries shall be considered side lot lines.
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Figure 11: Reverse curve lot
For all double frontage lots with Streets on opposite sides of the parcel, except for those parcels abutting Main
Street, the front lot line shall be the parcel boundary with the greatest length of Street frontage and the opposing
lot boundary shall be the rear lot line.
Figure 12: Double frontage lot
For double frontage lots with equal length street frontages, the front lot line shall mirror the front lot lines of the
adjoining lots to the extent practical.
For double frontage lots abutting Main Street, the front lot line shall be the lot line adjoining Main Street.
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The Community Development Director shall resolve any discrepancies or situations where the foregoing text does
not provide definitive clarity by issuance of a recordable administrative determination.
(3) Determining required setbacks adjacent to streets or rights-of-way. When a property does not extend
into an adjacent public or private right-of-way or street easement, the required setback shall be
measured from the lot line.
When a property extends into an adjacent public or private right-of-way or street easement, the
required setback for that portion of the lot shall be measured from the edge of the right-of-way or
street easement closest to the proposed structure.
Figure 13: Required setback from a right-of-way or street easement
(4) Combined Setbacks. Where zoning provisions require a combined yard setback (either front-rear or
side-side), the narrowest point on each yard shall be the basis for measuring the combined setback. A
combined yard requirement may not be met by staggering the required yard setbacks.
For example, if a lot requires a combined side-yard setback of thirty (30) feet, with a minimum of ten
(10) feet on either side, Figure 14 shows compliance with the requirement - one (1) side yard is ten (10)
feet, the other is twenty (20) feet, and each side yard setback is consistent from front to rear.
Given the same example, Figure 15 meets the individual ten (10) feet setback requirements, but the
combined setback is staggered and is not consistent from front to rear. This example does not meet
the combined setback requirement.
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(5) Allowed Projections into Setbacks. Setback areas shall be unobstructed above and below ground except
for the following allowed projections:
a. Above or below ground utilities, including transformers and vaults, below-grade heating or
cooling conduit or infrastructure such as a ground-source heat pump system, below-grade dry
wells or other at-grade or below-grade drainage infrastructure.
b. Trees and vegetation.
c. Artwork, sculpture, seasonal displays.
d. Flagpoles, mailboxes, address markers.
e. Foundation footers, soil nails or below-grade tiebacks, and similar improvements necessary for
the structural integrity of a building or other structures.
f. The minimum projection necessary to accommodate exterior mounted utility junctions, meters,
cable boxes, vent flues, standpipes, and similar apparatus and including any protective structure
as may be required by the utility provider.
g. Building eaves, bay windows, window sills, and similar architectural projections up to eighteen
(18) inches as measured from the setback boundary.
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h. The minimum projection necessary to accommodate light wells and exterior basement stairwells
as required by adopted Building or Fire Codes as long as these features are entirely recessed
behind the vertical plane established by the portion of the building façade(s) closest to any
Street(s).
If any portion of the feature projects into the setback, the entire feature may be no larger than
the minimum required.
Features required for adjacent subgrade interior spaces may be combined as long as the
combined feature represents the minimum projection into the setback. There is no vertical depth
limitation for these features.
This exemption does not apply to Areaways. This exemption does not apply to light wells and
exterior basement stairwells which are not required by adopted Building or Fire Codes.
i. The minimum projection necessary to accommodate an exterior-mount fire escape to an existing
building, as may be required by adopted Building or Fire Codes.
j. Uncovered porches, landscape terraces, slabs, patios, walks and similar features, which do not
exceed six (6) inches vertically above or below the surrounding finished grade for the entire
feature.
k. Landscape walls, berms, retaining walls, stairways and similar structures, which do not exceed
thirty (30) inches vertically above or below the lower of natural or finished grade. Improvements
may be up to thirty (30) inches above and below grade simultaneously, for up to a sixty (60) inch
total. Improvements may exceed thirty (30) inches below grade if determined to be necessary for
the structural integrity of the improvement. Berms are prohibited in the front yard setback.
l. Drainage swales, stormwater retention areas, bio retention areas, rain collection systems, and
similar stormwater retention, filtration or infiltration devices or facilities are permitted in
setbacks as long as the finished grade of the top of the improvement does not exceed thirty (30)
inches vertically above or below the surrounding finished grade. Stormwater improvements or
portions thereof may be buried and exceed thirty (30) inches below grade as long as the finished
grade above the facility does not exceed thirty (30) inches vertically above or below the
surrounding finished grade. These features may be up to thirty (30) inches above and below
finished grade simultaneously.
m. Hot tubs, spas, pools, water features, and permanently affixed outdoor grills, furniture, seating
areas, and similar permanent structures shall have the following requirements:
1. Prohibited between any lot line adjacent to a street and any structure; and
2. Shall be located at least double the minimum setback for a primary structure from any lot
line adjacent to a street; and
3. If visible from the street, these features shall be screened in accordance with Section
26.575.050, Fence Materials, with natural features, or by other means determined
appropriate by the Community Development Director ; and
4. If located within a setback not adjacent to a street, these features shall not exceed thirty
(30) inches above or below finished grade. These features may be up to thirty (30) inches
above and below finished grade simultaneously. Improvements may exceed thirty (30)
inches below grade if necessary for the structural integrity of the improvement.
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n. Heating and air conditioning equipment and similar mechanical equipment, but excluding
generators, shall have the following requirements:
1. Prohibited between any lot line adjacent to a street and any structure; and
2. Shall be located at least double the minimum setback for a primary structure from any lot
line adjacent to a street; and
3. If visible from the street, these features shall be screened in accordance with Section
26.575.050, Fence Materials, with natural features, or by other means determined
appropriate by the Community Development Director; and
4. If located within a setback not adjacent to a street, these features shall not exceed thirty
(30) inches above and forty-eight (48)inches below finished grade. These features may be
up to thirty (30) inches above and forty-eight (48) inches below finished grade
simultaneously.
o. The height and placement of energy efficiency or renewable energy production systems and
equipment, which are located adjacent to or independent of a building shall be established by
the Planning and Zoning Commission pursuant to the procedures and criteria of Chapter 26.430,
Special Review. These systems are discouraged between any lot line adjacent to a street and any
structure. For energy production systems and equipment located on top of a structure, see
subsection (f)(4).
p. The Community Development Director may approve exceptions to the requirements of
subsections m., n., and o., above. The Community Development Director must first determine
that the visual impact of the exemption is minimal, that no other reasonable option exists, or
that there is a significant increase in efficiency gained as a result of flexibility. Approval may be
granted during building permit review, or as part of a site-specific development approval.
q. Fences and hedges less than forty-two (42) inches in height, as measured from finished grade,
are permitted in all required yard setbacks. Fences and hedges up to six (6) feet in height, as
measured from finished grade, are permitted only in areas entirely recessed behind the vertical
plane established by the portion of the building facade which is closest to the Street. This
restriction applies on all Street-facing facades of a parcel. (Also see Section 26.575.050,
Supplementary Regulations for limitations on fence materials.)
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r. Driveways not exceeding twenty-four (24) inches above or below finished grade within any
setback of a yard facing a Street. Within all other required setbacks, finished grade of a driveway
shall not exceed thirty (30) inches above or below finished grade.
s. Parking may occur in required setbacks if within an established driveway or parking area and the
curb cut or vehicular access is from an alleyway, if an alleyway abuts the property, or has
otherwise been approved by the City.
t. Non-permanent features which are not affixed to the ground such as movable patio furniture,
outdoor seating or a picnic table, barbeque grills, children's play equipment, and similar non-
permanent features which are not affixed to the ground. This exemption shall not allow storage
sheds or containers.
u. Wildlife-resistant Trash and Recycling enclosures located in residential zone districts shall be
prohibited in all yards facing a Street. These facilities may be placed within non-street facing
yards if the enclosure is the minimum reasonably necessary in both height and footprint, is an
unconditioned space not integrated with other structures on the property, and serves no other
purpose such as storage, garage space, or other purposes unrelated to protecting wildlife.
Wildlife-resistant trash and recycling enclosures located in commercial, mixed-use, or lodging
zone districts are not exempt from setback requirements and shall comply with zone district
requirements for Utility/Trash/Recycle areas.
Temporary intermittent placement of trash and recycling containers in or along yards facing a
Street is allowed. For example, on "trash day."
Enclosures shall be located adjacent to the alley where an alley borders the property and shall
not be located in a public right-of-way. Unless otherwise approved by the Historic Preservation
Commission, enclosures shall not abut or be attached to a historic structure. Enclosures may
abut other non-historic structures.
For projects that are proposed to be, or are currently one hundred (100) percent Deed Restricted
Affordable Housing, Wildlife-resistant trash and recycling enclosures shall be located along the
alley, when possible. If no alley exists, the enclosure may be located in a street facing yard if
located and designed in a way to minimize visual impact of the enclosure, ensure efficient use of
the enclosure, and the minimum size necessary in both height and footprint to meet the
requirements of Title 12 of the Municipal Code.
v. Generators are prohibited between and structure and the street and within any setback.
Exceptions may be made by the Community Development Director in accordance with Section
26.575.020(e)(5)j.
(f) Measuring Building Heights.
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(1) For properties in the Commercial Core (CC), Commercial (Cl), Commercial Lodge (CL), Neighborhood
Commercial (NC) and Service Commercial Industrial (SCI) Zone Districts, the height of the building shall
be the maximum distance between the ground and the highest point of the roof top, roof ridge,
parapet, or top-most portion of the structure. See subsection (3), below, for measurement method.
(2) For properties in all other Zone Districts, the height of the building shall be measured according to the
pitch of the roof as follows. See subsection (3), below, for measurement method.
a. Flat roofs or roofs with a pitch of less than 3:12. The height of a building with a roof pitch of less
than 3:12 shall be measured from the ground to the top-most portion of the structure.
Figure 18: Measuring height for flat roofs or roofs with less than 3:12 pitch
b. Roofs with a pitch from 3:12 to 7:12. The height of a building with a roof pitch from 3:12 to 7:12
shall be measured from the ground to the point of the roof vertically halfway between the eave
point and the ridge. There shall be no limit on the height of the ridge.
c. Roofs with a pitch greater than 7:12. The height of a building with a roof pitch greater than 7:12
shall be measured from the ground to the point of the roof vertically one-third (⅓) of the
distance up from the eave point to the ridge. There shall be no limit on the height of the ridge.
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Figure 19: Measuring height for roofs with pitch from 3:12 to 7:12
Figure 20: Eave Point and Exterior Sheathing of a Roof
For roofs with multiple pitches within one (1) vertical plane, the height of the roof shall be measured by drawing a
line within a vertical section between the ridge and the Eave Point(s) and then applying the methodology for the
resulting pitch of said line(s) as described above.
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d. For barrel-vault roofs, height shall be measured by drawing a line within a vertical section
between the top-most point of the roof and the Eave Point(s) and then applying the
methodology for the resulting pitch of said line(s) as described above.
e. For "shed" roofs with a single-pitch, the methodology for measuring shall be the same as
described above according to the slope of the roof and by using the highest point of the roof as
the ridge.
f. For mansard roofs, height shall be measured to the flat roof as described above.
g. Dormers shall be excluded from the calculation of height if the footprint of the dormer is fifty
(50) percent or less of the roof plane on which the dormer is located and the ridge of the dormer
is not higher than the ridge of the roof on which it is located. If there are multiple dormers on
one (1) roof plane, the aggregate footprint shall be used. Otherwise, dormers shall be included in
the measurement of height according to the methods described above.
h. Butterfly roofs shall be measured in accordance with shed roof methodology.
(3) Height Measurement Method. In measuring a building for the compliance with height restrictions, the
measurement shall be the maximum distance measured vertically from the ground to the specified
point of the building located above that point, as further described below:
a. Measuring height along the perimeter of the building. At each location where the exterior
perimeter of a building meets the ground, the measurement shall be taken from the lower of
natural or finished grade. Building permit plans must depict both natural and finished grades.
b. Measuring height within the footprint of the building. For the purposes of measuring height
within the footprint of a building, areas of the building within fifteen (15) horizontal feet of the
building's perimeter shall be measured using the perimeter measurement, as described above. In
all other areas, the natural grade of the site shall be projected up to the allowable height and the
height of the structure shall be measured using this projected topography.
In instances where the natural grade of a property has been affected by prior development
activity, the Community Development Director may accept an estimation of pre-development
topography prepared by a registered land surveyor or civil engineer. The Director may require
additional historical documentation, technical studies, reports, or other information to verify a
pre-development topography.
If necessary, the Community Development Director may require an applicant document natural
grade, finished grade, grade being used within the footprint of the building, and other relevant
height limitation information that may need to be documented prior to construction.
c. Measuring to the roof- The high point of the measurement shall be taken from the surface of a
structure's roof inclusive of the first layer of exterior sheathing or weatherproofing membrane
but excluding exterior surface treatments such as shakes, shingles, fire proofing, exterior
insulation, a second layer of exterior sheeting, or other veneer treatments or ornamentation.
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Figure 21: Roof Assembly Example
When measuring roofs to a point between the ridge and the eave point, the eave point shall be the point where
the plane of a roof intersects the plane of the exterior wall. The roof and wall planes shall be of the nominal
structure, excluding all exterior treatments.
Figure 22: Eave Point and Exterior Sheathing of a Roof
(4) Allowed Exceptions to Height Limitations.
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a. Chimneys, flues, and similar venting apparatus. Chimneys, flues, vents, and similar venting
apparatus may extend no more than ten (10) feet above the height of the building at the point
the device connects. For roofs with a pitch of 8:12 or greater, these elements may not extend
above the highest ridge of the structure by more than required by adopted building codes or as
otherwise approved by the Chief Building Official to accommodate safe venting. To qualify for
this exception, the footprint of these features must be the minimum reasonably necessary for its
function the features must be combined to the greatest extent practical. Appurtenances such as
hoods, caps, shields, coverings, spark arrestors, and similar functional devices or ornamental do-
dads shall be contained within the limitations of this height exception.
On structures other than a single-family or duplex residential building or an accessory building,
all Chimneys, flues, vents, and similar venting apparatus should be set back from any Street
facing façade of the building a minimum of twenty (20) feet and the footprint should be
minimized and combined to the greatest extent practicable.
b. Communications Equipment. Antennas, satellite dishes, and similar communications equipment
and devices shall comply with the limitations of Section 26.575.130, Wireless Telecommunication
Services Facilities and Equipment.
c. Elevator and Stair Enclosures. On structures other than a single-family or duplex residential
building or an accessory building, elevator overrun enclosures and stair enclosures may extend
up to five (5) feet above the specified maximum height limit.
Elevator and stair enclosures may extend up to ten (10) feet above the specified maximum height
limit if set back from any Street facing façade of the building a minimum of twenty (20) feet and
the footprint of the elevators or stair enclosures are minimized and combined to the greatest
extent practicable.
For single-family and duplex residential buildings and for accessory buildings, elevator and stair
enclosures are not allowed a height exception.
d. Rooftop Railings. On any structure other than a single-family or duplex residential building,
rooftop railings and similar safety devices permitting rooftop access may extend up to five (5)
feet above the height of the building at the point the railing connects. To qualify for this
exception, the railing must be the minimum reasonably necessary to provide adequate safety and
building code compliance and the railing must be fifty (50) percent or more transparent. All
railings shall be set back from any Street facing facade of the building by an amount equal to the
height of the railing.
For single-family and duplex residential buildings, rooftop railings shall not be allowed a height
exception.
e. Mechanical Equipment. Heating, ventilation, and air conditioning systems, and similar mechanical
equipment or utility apparatus located on top of a building may extend up to six (6) feet above
height of the building at the point the equipment is attached. This allowance is inclusive of any
pad the equipment is placed on, as well as any screening. Mechanical equipment shall be
screened, combined, and co-located to the greatest extent practicable.
On structures other than a single-family or duplex residential building or an accessory building,
all mechanical equipment shall be set back from any Street facing façade of the building a
minimum of fifteen (15) feet.
f. Energy Efficiency or Renewable Energy Production Systems and Equipment. Energy efficiency
systems or renewable energy production systems and equipment including solar panels, wind
turbines, or similar systems and the system's associated equipment which is located on top of a
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building may extend up to six (6) feet above the height of the building at the point the equipment
is attached.
On any structure other than a single-family or duplex residential building or an accessory
building, these systems may extend up to ten (10) feet above height of the building at the point
the equipment is attached if set back from any Street facing façade of the building a minimum of
twenty (20) feet and the footprint of the equipment is minimized and combined to the greatest
extent practicable.
The height and placement of energy efficiency or production systems which are not located on
top of a building (located independent of a building) shall be established by the Planning and
Zoning Commission pursuant to the procedures and criteria of Chapter 26.430, Special Review.
(Also see setback requirements for these systems at subsection (e)(5).)
g. Church spires, bell towers and like architectural projections on Arts, Cultural and Civic buildings
may extend over the height limit as may be approved pursuant to Commercial Design Review.
h. Flag poles may extend over the specified maximum height limit.
i. Exceptions for buildings on slopes. For properties with a slope that declines by ten percent (10%)
or greater from the front lot line, the maximum height of a building's front (street-facing) facade
may extend horizontally for the first ten (10) feet of the building's depth.
For properties located in the geographical area bounded by Durant Street, Main Street, Monarch
Street and Original Street and have a maximum elevation change of three (3) feet, the maximum
height measurement as determined from the highest point of the lot may extend the entire
width or length of the lot. See Figure A, below, where "X'" is the measured height.
Figure A: Measurement on a Slope
j. Exceptions for lightwells and basement stairwells. A basement stairwell required by Building Code
for egress shall not be counted towards maximum permissible height. On street facing facades
the minimum size lightwell entirely recessed behind the vertical plane established by the portion
of the building façade(s) closest to any Street(s), and enclosed on all sides to within eighteen (18)
inches of the first floor level (e.g. not a walk-out style light well) shall not be counted towards
maximum permissible height. On non-street facing facades a lightwell that is no more than one
hundred (100) square feet shall not be counted towards maximum permissible height. This
exception does not apply to lightwells and stairwells that are located within a setback.
For properties that contain an areaway that counts toward the pedestrian amenity requirement,
the qualifying areaway shall not be counted towards maximum permissible height. See Figure B,
below, where "X'" is the measured heights and "Y'" is not counted if the subgrade area counts as
pedestrian amenity.
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Figure B: Measurement of heights with subgrade pedestrian amenity
The Historic Preservation Commission is authorized to grant an exception to height for lightwells
larger than one hundred (100) square feet on historic landmark properties that contain a historic
resource upon a finding that the following conditions are met:
1. Lightwell is not easily visible from the right-of-way.
2. Approval of the exemption supports the preservation of the historic resource.
k. For commercial, lodge, or mixed-use buildings located in the Commercial Core (CC), Commercial
(C-1), or Neighborhood Commercial (NC) zone districts, decorative, non-functional architectural
elements such as a parapet, cornice, spire, pediment, are exempted from height measurement
up to twenty-four (24) inches only if approved by the Planning and Zoning Commission or Historic
Preservation Commission as part of a Commercial Design Review. This exemption shall not be
combined with any other height exemptions.
l. Permanent Rooftop Amenities. Permanent rooftop amenities, such as built-in wet bars, built-in
barbeque grills, cabinets, sinks, fire pits, pools, hot tubs, etc. shall be permanently installed and
shall meet the following height and setback requirements to qualify for a height exemption. This
only applies to a mixed use, lodge, or commercial building located in the Commercial Core (CC)
Zone District, Mixed Use (MU) Zone District, the Commercial (C-1) Zone District, the Lodge (L)
Zone District, the Neighborhood Commercial (NC) Zone District, or the Commercial Lodge (CL)
Zone District. Permanent rooftop amenities may extend up to five (5) feet above height of the
building at the point the equipment is attached to the roof. This allowance is inclusive of any pad
the equipment is placed on. A trellis with a maximum height of ten (10) feet and a maximum
floor area of no more than five (5) percent of the useable deck area is permitted. All permanent
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rooftop amenities shall be set back from any Street facing façade of the building by a minimum of
ten (10) feet.
m. Exceptions for skylight and light tubes. A skylight or light tube typical of industry standards and
meeting minimum Building Code standards shall not be counted towards maximum permissible
height.
(g) Measuring Site coverage. Site coverage is typically expressed as a percentage. When calculating site coverage
of a structure or building, the exterior walls of the structure or building at ground level should be used. When
measuring to the exterior walls, the measurement shall be taken from the exterior face of framing, exterior
face of structural block, or similar exterior surface of the nominal structure excluding sheathing, vapor
barrier, weatherproofing membrane, exterior-mounted insulation systems, and excluding all exterior veneer
and surface treatments such as stone, stucco, bricks, shingles, clapboards or other similar exterior veneer
treatments. Porches, roofs or balcony overhangs, cantilevered building elements and similar features
extending directly over grade shall be excluded from maximum allowable site coverage calculations.
(h) Measurement of Net Leasable Area and Net Livable Area. The calculation of net leasable area and net livable
area shall include all interior space of a building measured from interior wall to interior wall, including
interior partitions. Net leasable area and net livable area shall be attributed to the lot or parcel upon which it
is developed. Net leasable area includes all interior areas which can be leased to an individual tenant with
the exceptions noted below. Net livable area includes those areas of a building that are used or intended to
be used for habitation with the exceptions noted below. Garages and carports are exempt from net leasable
area and net livable area calculations.
(1) Permanently installed interior airlock spaces are exempt from the calculation of net leasable space up
to a maximum exemption of one hundred (100) square feet. Seasonal airlocks of more than ten (10)
square feet, installed on the exterior of a building, shall be considered net leasable area and shall be
subject to all requirements of the Land Use Code, including employee mitigation, prorated according to
the portion of the year in which it is installed.
(2) Unless specifically exempted through other provisions of this Title, outdoor displays, outdoor vending,
and similar commercial activities located outside (not within a building) shall also be included in the
calculation of net leasable area. The calculation of such area shall be the maximum footprint of the
display or vending apparatus. For vending carts or similar commercial activities requiring an attendant,
the calculation shall also include a reasonable amount of space for the attendant. Exterior decks and
exterior seating are not included in the calculation of net leasable area. Vending machines, gas pumps,
and similar devices without an attendant shall not be considered net leasable area.
The calculation of net leasable area and net livable area shall exclude areas of a building that are integral to the
basic physical function of the building. All other areas are attributed to the measurement of net leasable
commercial space or net livable area. When calculating interior stairways or elevators, the top most interior level
served by the stairway or elevator is exempt from net livable or net leasable area calculations.
Shared areas that count toward net leasable area and net livable area shall be allocated on a proportionate basis
of the use category using the percentages that are generated pursuant to Section 26.575.020(d)(14), Allocation of
non-unit space in a mixed use building.
Examples:
a. A broom closet of a minimum size to reasonably accommodate the storage of janitorial supplies
for the entire building is considered integral to the physical function of the building and does not
count toward net leasable area.
b. A shared commercial storage area that is larger than needed for the basic functionality of the
building counts toward net leasable area because it is useable by the businesses.
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c. A shared stairway and a shared circulation corridor (that access more than one (1) use) are
integral to the physical function of the building and do not count in the measurement of net
livable area or net leasable area.
d. A stairway that is entirely within one (1) residential unit counts toward the measurement of net
livable area.
e. A private elevator that serves more than one (1) residential unit, and does not provide access to
other uses, does not count toward the measurement of net livable area.
f. A private elevator that serves only one (1) residential unit, and does not provide access to other
uses, counts toward the measurement of net livable area.
g. A shared mechanical room that is larger than the minimum space required to reasonably
accommodate the mechanical equipment counts toward the measurement of net livable area or
net leasable area as applicable. The area of the mechanical room that is the minimum size
required for the mechanical equipment does not count in net livable area or net leasable area.
(i) Exceptions for Energy Efficiency. The Community Development Director may approve exceptions to the
dimensional restrictions of this Section to accommodate the addition of energy production systems or
energy efficiency systems or equipment in or on existing buildings when the site is constrained, or it's
recognized flexibility is warranted to improve efficiency of the equipment or structure. The Community
Development Director must first evaluate that the visual impact of the exemption is minimal and that no
other reasonable way to implement energy production or efficiency exists that is more effective and less
impactful. Exception for Energy Efficiency may be approved during building permit or land use review.
(j) Exceptions for Building Code Compliance. The Community Development Director may approve exceptions to
the dimensional restrictions of this Section to accommodate improvements required to achieve compliance
with building, fire, energy, or accessibility codes in or on existing buildings when no other practical solution
exists. The Community Development Director must first evaluate that the visual impact of the exemption is
minimal and that no other reasonable way to implement code compliance exists that is more effective and
less impactful. Exception for Building Code Compliance may be approved during building permit review or
land use review.
(k) Appeals. An applicant aggrieved by a decision made by the Community Development Director regarding this
Calculations and Measurements Section may appeal the decision to the Administrative Hearing Officer,
pursuant to Chapter 26.316.
(Ord. No. 44-1999, § 7; Ord. No. 55-2000, § 14; Ord. No. 56-2000, §§ 5, 6, 8; Ord. No. 25-2001, §§ 6, 7; Ord. No. 46-
2001, § 4; Ord. No. 55, 2003, §§ 2—4; Ord. No. 12-2006, § 19; Ord. No. 12, 2007, § 32; Ord. No. 27-2010, § 1; Ord.
No. 12-2012, § 3; Ord. No. 25-2012, § 4; Ord. No. 7-2014; §§ 1-9; Ord. No. 31-2014, § 2; Ord. No. 4-2015, § 1; Ord.
No. 46-2015, §§ 12-20; Ord. No. 30, 2016, § 6; Ord. No. 8, 2017, § 2; Ord. No. 13-2022, § 9, 6-28-2022)
59
STAFF REPORT
TO: Mayor and City Council
FROM: Dan Folke, Planning Director
THROUGH: Ben Anderson, Community Development Director
Gillian White, Historic Preservation Officer, Principal Planner
MEETING DATE: April 13, 2026
SUBJECT: Discussion with Historic Preservation Commission
__________________________________________________________________
INTENDED OUTCOME & SUMMARY:
The Historic Preservation Commission requested a joint work session with the City
Council to review and discuss the Transferable Development Rights (TDR) program and
the desire to review and consider changes to the adopted Historic Preservation Design
Guidelines. The desired outcome is a discussion on the TDR program and if potential
changes to the program should be explored. Similarly, staff and the Commission
believe updates to the Historic Preservation guidelines are needed and are looking for
input from City Council.
DISCUSSION:
The TDR program was created in 2003, Ordinance No. 54 which created Chapter
26.535 Transferable Development Rights (TDR). The stated purpose of the TDR
program:
The purpose of this Chapter is to encourage the preservation of historic
landmarks, those properties listed on the Aspen Inventory of Historic Landmark
Sites and Structures and those properties identified on the AspenModern Map,
within the City by permitting those property owners to sever and convey, as a
separate development right, undeveloped floor area to be developed on a
different property within the City. The program enables standard market forces
and the demand for residential floor area, to accomplish a community goal of
preserving Aspen's heritage as reflected in its built environment.
The first TDR certificate was approved in 2004 and the program has resulted in the
creation of 135 certificates at 39 properties. Of the 135 certificates, 68 (50%) have
60
landing sites. All of the sending and receiving sites have been mapped and are
attached as Exhibit A.
Sales information has been disclosed on 62 of the certificates. Sales of the 250 square
foot certificates ranged from $153,000 to $700,000. The average sale price is $274,818
or $1,099.27 per square foot. The first sale over $400,000 occurred in 2021, while the
first sale over $600,000 was in 2023. The most recently reported certificate sales in
February, 2025 were for $700,000 each. The certificate values are shown on the
attached line graph, Exhibit B.
The current Historic Preservation Design Guidelines were originally adopted around
2014 and last revised in 2024. Staff and the Commission are interested in reviewing the
guidelines to align with current construction trends and desired materials. Community
priorities such as Fire Mitigation, Energy Efficiency and Electrification could also warrant
guideline revisions.
ATTACHMENTS:
Exhibit A: Map of Transferable Development Right Sending and Receiving Sites
Exhibit B: Transferable Development Right Certificate Valuation over Time
Exhibit C: Historic Preservation Design Guidelines
CITY MANAGER COMMENTS:
61
Date: 3/31/2026
Geographic Information Systems
This map/drawing/image is a graphical
representation of the features
depicted and is not a legal representation.
The accuracy may change
depending on the enlargement or reduction.
Copyright 2026 City of Aspen GIS
Legend
Aspen City Limits - Map Service
TDR Sending Points
TDR Landing Points
0 1,000 2,000500
Feet
When printed at 11"x17"
4
Scale: 1:24,000
Transferable
Development Rights
City of Aspen GIS, Pitkin County, Esri, TomTom, Garmin, SafeGraph,
GeoTechnologies, Inc, METI/NASA, USGS, Bureau of Land Management,
EPA, NPS, US Census Bureau, USDA, USFWS
62
63
City of Aspen
Historic Preservation
Design Guidelines
64
65
Historic Preservation
Design Guidelines
Revised 05/2024
66
67
table of contents
introduction
historic overview
design guidelines:
rehabilitation
appendix
Why Preserve Historic Resources 8
Purpose of the Design Guidelines 10
How to Use the Guidelines 10
Design Review Process 13
Aspen Historic Overview 16
Architectural Styles in Aspen 21
Chapter 2: Building Materials 52
Chapter 3: Windows 55
Chapter 4: Doors 59
Chapter 5: Porches & Balconies 63
Chapter 6: Architectural Details 66
Chapter 7: Roofs 68
Chapter 8: Secondary Structures 73
design guidelines:
new construction
Chapter 9: Excavation, Building Relocation, & Foundations 76
Chapter 10: Building Additions 79
Chapter 11: New Buildings on Landmarked Properties 85
Secretary of the Interior’s Standards
for Historic Preservation 94
design guidelines:
general
Chapter 12: Accessibility, Architectural Lighting,
Mechanical Equipment, Services Areas, & Signage 90
design guidelines:
context
Chapter 1: Site Planning & Landscape Design 36
68
69
I ntroduction
70
8 • City of Aspen • Historic Preservation Design Guidelines
Aspen is a unique community, rich with history,
dramatic landscapes, a vibrant economy, and vital
cultural scene. Each of these elements contributes
to the appeal of the City and enhances its livability.
Within this context, the preservation of historic
resources is a high priority. This policy is articulated
in the Aspen Area Community Plan and in ordinances
that address protection of landmarked properties and
historic districts.
This document provides background on the City’s
preservation program and local history and then
presents design guidelines that articulate policies for
the treatment of locally-designated historic properties
and districts.
Why Preserve Historic Resources
Across the nation, thousands of communities
promote historic preservation because doing so
contributes to neighborhood livability, variety, and
quality of life, minimizes negative impacts on the
environment and yields economic rewards. These
same reasons apply in Aspen. Preservation of the
built environment in Aspen provides a fundamental
link to the past. Many of the buildings tell the story
of Aspen’s unique historical development. Preserving
these resources creates a sense of place for those
who live here and provides visitors a connection with
this unique heritage.
Construction Quality
Many of the historic structures in the City are of high
quality construction. Other buildings are more modest,
but even so may have used lumber from mature trees
that were properly seasoned and typically milled to
full dimension, which often yields stronger framing.
Historic masonry walls were carefully laid, resulting in
buildings with considerable stability.
Many older structures were thoughtfully detailed and
the finishes of materials, including fixtures, wood
floors and trim, were of high quality and exemplify
hand craftsmanship that is more unusual today.
Some AspenModern structures represent early use of
building technologies that continue to be favored.
Adaptability
Owners frequently find that the floor plans of historic
buildings easily accommodate modern lifestyles and
support a diversity of populations. Many rooms are
large, permitting a variety of uses while retaining
the overall historic character of the structure. Even
historic buildings that are smaller in scale often have
lots that can accommodate additions, if needed.
Livability and Quality of Life
When groups of older buildings occur as a historic
district, such as along Main Street or the Commercial
Core in Aspen, they create a street scene that is
pedestrian friendly, and encourages walking and
neighborly interaction. Mature trees and decorative
architectural features also contribute to a sense of
identity that is unique for each historic neighborhood—
an attribute that is rare and difficult to achieve in
newer areas of a city. These therefore are desirable
places to live and work.
Environmental Benefits
Preserving a historic structure is sound environmental
conservation policy because “recycling” saves energy
and reduces the need for producing new construction
materials. Three types of energy savings occur:
IntroductIon
i ntroduction
Note: Not every guidelines will apply to each
project, and some balancing of the guidelines
must occur on a case-by-case basis. The
Aspen Historic Preservation Commission (HPC)
must determine that a sufficient number of the
relevant guidelines have been adequately met in
order to approve a project proposal. It must be
emphasized that these are only guidelines and
they are not applicable in all cases, and need to
be weighed with the practicality of the measure.
71
City of Aspen • Historic Preservation Design Guidelines • 9
•First, energy is not consumed to demolish the
existing building and dispose of the resulting
debris.
•Second, energy is not used to create new building
materials, transport them and assemble them on
site.
•Finally, the embodied energy which was used to
create the original building and its components,
is preserved.
By reusing older buildings, pressure is reduced to
harvest new lumber and other materials that may
have negative effects on the environment of other
locales where these materials are produced.
Economic Benefits
Historic resources are finite and cannot be replaced,
making them precious commodities that many buyers
seek. Preservation adds value to private property.
Many studies across the nation document that, where
local historic districts are established, property values
typically rise, or at least are stabilized. In this sense,
designation of a historic district appears to protect
investment. Property owners within the district know
that the time and money they spend on improving
their properties will be matched with similar efforts
on surrounding lots. Arguably, this applies to Aspen
as well.
Nationwide studies prove that preservation projects
also contribute more to the local economy than do
new building programs because each dollar spent
on a preservation project has a higher percentage
devoted to labor and to the purchase of materials
available locally. By contrast, new construction
typically has a higher percentage of each dollar spent
devoted to materials that are produced outside of
the local economy and to special construction skills
that may be imported. When money is spent on
rehabilitating a building, it has a higher “multiplier
effect,” keeping more money circulating in the
community. Rehabilitation therefore, provides more
jobs for Aspen area residents.
Heritage Tourism
Preservation minded communities are among
the leading tourist destinations. Aspen has an
authenticity that visitors appreciate. There are many
opportunities to connect with the history of Aspen
as a tourist and this contributes to longer stays and
repeat visits.
Incentives for Preservation
While the economic benefits are substantial, special
incentives also exist to help offset potential added
costs of appropriate rehabilitation procedures.
Income tax credits are offered at the state and federal
levels for appropriate rehabilitation. Eligible projects
also can qualify for the Colorado Historical Society’s
State Historical Fund, a substantial opportunity for
owners of commercial and significant residential
properties.
The City also offers financial bonuses which are
available for historic landmarks. The Aspen Historic
Preservation Commission (HPC) has the ability to
award zoning bonuses to historic landmarks.
Responsibility of Ownership
Ownership of a historic property carries both the
benefits described above and a responsibility to
respect the historic character of the resource and its
setting. While this responsibility does exist, it does not
automatically translate into higher construction or
maintenance costs. Ultimately, residents and property
owners should recognize that historic preservation
is a long-range community policy that promotes
economic wellbeing and overall viability of the City
at large and that they play a vital role in helping to
implement that policy through careful stewardship of
the area’s historic resources.
Levels of Historic Designation in Aspen
Local Landmark
The City has identified approximately 300 historic
resources, including buildings, structures, parks,
cemeteries, and bridges as historic landmarks.
Because there was a long period of economic
depression at the turn of the 20th century, historic
development in Aspen generally occurred either in the
silver mining era (these resources are termed Aspen
Victorian) or around World War II (these resources are
termed AspenModern).
The local register designation process is established
through the police powers of Aspen’s zoning
ordinance. Criteria for designation are set forth in
city codes and designated properties are subject
to protections outlined in the ordinance, including
demolition and design review. In general, any exterior
alteration to an inventoried property must be reviewed
and approved before work can begin.
District Designation
Currently, the City of Aspen has two locally designated
historic districts, the Main Street Historic District, and
the Commercial Core Historic District. The districts
were created to preserve the character of entire
IntroductIon
72
10 • City of Aspen • Historic Preservation Design Guidelines
IntroductIon
neighborhoods. In general, any demolition, exterior
alteration, or construction on a property within a
historic district must be reviewed and approved
before work can begin.
National Register Listing
The National Register of Historic Places is a list of
sites and properties of historic significance that is
maintained by the Secretary of the Interior. Properties
so listed may have national significance, but they
may also be listed if they are determined to have
significance at a state or local level. The National
Register is administered by the National Park Service
and nominations are submitted through the State
Historic Preservation Officer in Denver, using criteria
adopted by the Secretary of the Interior. Properties
listed in the National Register may be eligible for federal
income tax credit incentives. Designated properties
are also protected from federally-funded projects
which might harm or alter the historic character.
Such federal projects must be reviewed for their
potential negative impact. In these cases, alterations
are reviewed by the National Park Service. Otherwise,
only the standard process for all Aspen landmarks
applies. The History Colorado website lists National
Register properties by county: historycolorado.org/
oahp/pitkin-county.
Purpose of the Design Guidelines
These design guidelines are specifically for
properties listed on the “Inventory of Historic Sites
and Structures,” inside and outside of the historic
districts. Additional guidelines for the Main Street and
Commercial Core Historic Districts are found in the
“Commercial, Lodging, and Historic District Design
Objective and Guidelines”, a separate document
available on aspenpitkin.com.
The design guidelines serve to reinforce the purpose
of the Historic Preservation Chapter in the Aspen
Land Use Code:
•Recognize, protect, and promote the retention
and continued utility of the historic buildings and
districts in the City.
•Promote awareness and appreciation of Aspen’s
unique heritage.
•Ensure the preservation of Aspen’s character
as an historic mining town, early ski resort and
cultural center.
•Retain the historic, architectural and cultural
resource attractions that support tourism and the
economic welfare of the community.
•Encourage sustainable reuse of historic
structures.
•Encourage voluntary efforts to increase public
information, interaction or access to historic
building interiors.
The design guidelines provide a basis for making
decisions about the appropriate treatment of historic
resources and compatible new construction. They
also serve as an educational and planning tool for
property owners and their design professionals who
seek to make improvements that may affect historic
resources.
How to Use the Guidelines
While the design guidelines are written such that they
can be used by the layman to plan improvements,
property owners are strongly encouraged to enlist
the assistance of qualified design and planning
professionals, including architects, landscape
architects, structural engineers, preservation
contractors, and preservation consultants to assure
that the work contemplated will help preserve the
historic character of the City.
Any affected property owner who plans to make
changes to the exterior of a building must obtain a
Certificate of No Negative Effect or a Certificate of
Appropriateness. In order to review each project in a
consistent manner, City Preservation Staff and the HPC
will use these guidelines as a basis for determining
the appropriateness of the work proposed.
How Many Guidelines Must Be Met?
Note that not every guideline will apply to each project,
and that some balancing of the guidelines must occur
on a case-by-case basis. City Staff or the HPC will
determine that a sufficient number of the relevant
guidelines have been adequately met in order to
approve a project proposal.
What is the Format of a Guideline?
The chapters containing design guidelines are
organized in a format that provides background
information as well as specific regulatory language.
Each of these chapters contains the following
components:
Policy Statement
A broad statement explaining the City’s basic
approach for the treatment of the design feature being
discussed. This statement provides the basis for the
73
City of Aspen • Historic Preservation Design Guidelines • 11
more detailed background information and design
guidelines that follow. In a case in which special
conditions in a specific project are such that the
detailed design guidelines do not appear to address
the situation, then this broad policy statement serves
as the basis for determining the appropriateness of
the proposed work.
Background Information
A discussion of the issues typically associated with
the specific design topic is presented next. This
may include technical information, such as factors
associated with the preservation of a historic building
material, as well as general preservation theory that is
relevant to the topic at hand.
Pertinent Sub-Topics
The sections that follow the background information
are divided into sub-topics. For example, in the chapter
addressing Building Materials, the sub-topics include:
treatment, repair and replacement. This organization
allows the user to quickly select the specific design
topics within a section that are relevant.
Design Guidelines
The specific design guidelines are presented as bold
face statements under each sub-topic. These are also
numbered to indicate their relative position within the
chapter and to aid in specific reference in the review
process. Also provided with the design guidelines are
supplementary requirements, which are bulleted (•)
statements. These supplementary statements clarify
the primary design guideline statement and may
suggest specific methods for complying with it.
How Were the Design Guidelines Developed?
The City’s first preservation guidelines were adopted in
1972. The guidelines have been revised and improved
multiple times taking community input and the
experience of the Historic Preservation Commission
into account. The design guidelines incorporate
concepts set forth in The Secretary of the Interior’s
Standards for the Treatment of Historic Properties
(listed in the Appendix)—a nationally accepted set of
basic preservation design principles. This document
is compatible with the Secretary of the Interior’s
Standards, while expanding on how these basic
preservation principles apply in Aspen.
The Concept of Historic Significance
What makes a property historically significant? It is
generally recognized that a certain amount of time
must pass before the historical significance of a
property can be evaluated. The National Register, for
example, requires that a property be at least 50 years
old or have extraordinary importance before it may be
considered. Aspen does not have a minimum age for
designation.
A property may be significant for one or more of the
following reasons:
•Antiquity
•Association with events patterns, trends, or people
that have contributed to local, state, regional, or
national history.
•Physical design associated with distinctive
characteristics of a building type, period, or
construction method.
•An example of an architect or master craftsman or
an expression of particularly high artistic values.
•Singular significance to the City.
•Integrity of location, design, setting, materials,
workmanship, feeling and association.
Period of Significance
Every historic building or district has a period of
significance—or the time span during which it gained
architectural, historical or geographical importance.
In most cases, a property is significant because it
represents or is associated with a particular period in
history. Frequently, this begins with its construction
date and continues through the peak of early
occupation. Building fabric and features that date
from the period of significance typically contribute to
the character of the structure or district.
Concept of “Integrity”
In addition to being historically significant, a property
also must have integrity—a sufficient percentage
of the structure must date from the period of
significance. The majority of the building’s structural
system and its materials should date from that time
and its key character defining features also should
remain intact. These may include architectural details
as well as the overall mass and form of the building.
It is these elements that allow a building or district to
be recognized as a product of its time.
Preservation Principles
While the guidelines in this document provide direction
for specific design issues, some basic principles form
the foundation for them. The following preservation
principles apply to all historic properties in Aspen.
IntroductIon
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12 • City of Aspen • Historic Preservation Design Guidelines
IntroductIon
Respect the historic design character of the
building.
Don’t try to change a building’s style or make it look
older than it really is. Confusing the character by
mixing elements of different styles is not appropriate.
Seek uses that are compatible with the historic
character of the building.
Uses that closely relate to the building’s original use
are preferred. Every reasonable effort should be made
to provide a compatible use for the building that will
require minimal alteration to the building and its site.
Protect and maintain significant features and
stylistic elements.
Distinctive stylistic features or examples of skilled
craftsmanship should be treated with sensitivity. The
best preservation procedure is to maintain historic
features from the outset so that intervention is not
required.
Repair deteriorated historic features, and
replace only those elements that cannot be
repaired.
Maintain the existing material, using recognized
preservation methods whenever possible. If
disassembly is necessary for repair or restoration, use
methods that minimize damage to original materials
and re-install in the existing configuration.
Selecting a Preservation Approach
Each preservation project is unique. A project may
include a variety of treatment techniques, including the
repair and replacement of features and maintenance
of those already in good condition. Some of the basic
preservation treatments are described in the section
that follows. In each case, it is important to develop
an overall strategy for treatment that is based on an
analysis of the building and its setting.
Analysis should begin with an investigation of the
history of the property. This may identify design
alterations that have occurred and may help in
developing an understanding of the significance
of the building as a whole, as well as its individual
components. Sources for historic information
include the City of Aspen Community Development
Department, the Aspen Historical Society, and two
City websites; aspenvictorian.com and aspenmod.
com. Denver Public Library Western History
Collection (digital.denverlibrary.org) and on-line fire
insurance maps from the turn of the century, Sanborn
Maps, (cudl.colorado.edu) are also helpful.
Historical research should be combined with an
on-site assessment of existing conditions. In this
inspection, identify those elements that are original
and those that have been altered. Also determine the
condition of individual building components.
Finally, list the requirements for continued use of
the property. Is additional space needed? Or should
the work focus on preserving and maintaining the
existing configuration?
In addition to the historical background, research
should also be done which identifies the preservation
incentives offered by the HPC. The preservation
incentives are a way for the property owner to improve
a project and make it more sympathetic to the historic
resource.
By combining an understanding of the history of the
building, its present condition, and the need for action,
one can then develop a preservation approach. When
doing so, consider the following terms:
Maintenance
Work that often focuses on keeping the property in
good condition by repairing features as deterioration
becomes apparent, using procedures that retain
the original character and finish of the features. In
some cases, preventive maintenance is executed
prior to noticeable deterioration. No alteration or
reconstruction is involved. Property owners are
strongly encouraged to maintain their property in
good condition so that more aggressive measures
of rehabilitation, restoration or reconstruction are not
needed.
Preservation
Preservation is keeping an existing building in good
condition by a careful program of maintenance and
repair. It will often include repair and stabilization
of materials and features in addition to regularly
scheduled maintenance.
Restoration
To restore, one reproduces the appearance of a
building exactly as it looked at a particular moment
in time; to reproduce a pure style—either interior or
exterior. This process may include the removal of
later work or the replacement of missing historic
features. A restoration approach is used on missing
details or features of a historic building when the
features are determined to be particularly significant
to the character of the structure and when the original
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City of Aspen • Historic Preservation Design Guidelines • 13
IntroductIon
configuration is accurately documented.
Rehabilitation
Rehabilitation is the process of returning a property
to a state which makes a contemporary use possible
while still preserving those portions or features of
the property which are significant to its historic,
architectural and cultural values. Rehabilitation
may include the adaptive reuse of the building and
constructing additions. Most good preservation
projects in Aspen may be considered rehabilitation
projects.
Adaptive Use
Converting a building to a new use that is different
from its original purpose is considered to be adaptive
use. For example, converting a residential structure to
offices is adaptive use. A good adaptive use project
retains the historic character of the building while
accommodating new functions.
While adaptive use allows the building owner to
convert the building to a purpose other than that
for which it was designed, it should be done with
respect to the original building form. For example, it
would be inappropriate to turn the living room of a
historic building into a bathroom. The reason for this
is that when the programmatic uses of a building are
drastically altered, this often results in a major change
to the original floor plan as well as to the exterior
appearance of the building. When adaptive use is
the preferred preservation alternative, the proposed
design should honor the original building function as
closely as possible.
Combining Preservation Strategies
Many successful projects that involve historic
structures in Aspen may include a combination of
preservation, restoration, and other appropriate
treatments. For example, a house may be adapted to
use as a restaurant, and in the process, missing porch
brackets may be replicated in order to restore the
original appearance, while existing original dormers
may be preserved.
Planning a Preservation Project
Once the basic approach to a project has been defined,
it is important to assess the property and to identify
any significant character-defining features and
materials. Retaining these elements, and then using
the guidelines to select an appropriate treatment
mechanism will greatly enhance the overall quality
of the preservation project. In making the selection
follow this sequence:
1.If a feature is intact and in good condition,
maintain it as such.
2.If the feature is deteriorated or damaged, repair
it to its original condition.
3.If it is not feasible to repair the feature, then
replace it with one that is the same or similar
in character (materials, detail, finish) to the
original one. Replace only that portion which is
beyond repair.
4.If the feature is missing entirely, reconstruct it
from appropriate evidence.
5.If a new feature or addition is necessary, design
it in such a way as to minimize the impact on
original features.
Design Review Process
The Aspen Historic Preservation Commission
The City Council appoints volunteers to the Aspen
Historic Preservation Commission (HPC). The HPC
is comprised of members who are city residents,
have an expressed interest and expertise in historic
preservation, and are knowledgeable about the
heritage of the City.
Some work is exempt from historic preservation review
and other work may qualify for an Administrative
Review by the Community Development Department.
Approval is generally not required for a change in
paint color or interior alterations. A Community
Development Department review includes work such
as signs, fences, roofs and repairs. More substantial
projects are reviewed by HPC.
Applicants are encouraged to participate in a pre-
application conference with the Historic Preservation
Officer (HPO), available in the Community
Development Department. At this conference, the
HPO will identify any necessary review process,
discuss approvals that may be needed from other city
boards, provide application forms, and suggest any
modifications which may make the application more
consistent with the standards and guidelines.
Importance of Acquiring a Permit
Once approvals are granted, a property owner may
Any contractor, superintendent, or owner/builder
wishing to receive a building permit to work on a
historic structure will be required to complete the
“Aspen/Pitkin County Preservation Awareness
Program” and receive a specialty license in
historic preservation.
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14 • City of Aspen • Historic Preservation Design Guidelines
IntroductIon
apply for a building permit. Obtaining a building
permit is a crucial step in any construction process.
If a city building or zoning inspector finds that work
is occurring without a permit, the work is stopped, or
“red tagged.” In the simplest situation, construction is
delayed; in more contentious cases, the work has to be
reversed or rebuilt, resulting in long delays, additional
fees and fines, and occasionally court appearances.
Undertaking an act of demolition on a landmarked
structure without HPC approval may result in a long
term suspension of building permits for the property.
Building permits are not only a way for the City to keep
track of applications, but they also serve as protection
for the owner. Obtaining a building permit means that
the work will be inspected to determine that it has
been executed correctly.
The HPC is deeply committed to its responsibilty in
protecting the visual memory of the community and
ensuring that historic resources are respected within
the evolution of the City.
There are many possible directions to take when
approaching a preservation project. The Commission
appreciates a clear explanation of context, how the
proposal contributes to a sense of place in the
community, and site analysis. An applicant should
explain their intent and approach and provide models,
story poles, material samples and other information
to assist the review process.
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H istoric o verview
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16 • City of Aspen • Historic Preservation Design Guidelines
Aspen has experienced several cycles of development
in its history, beginning with the mining industry of
the 1880s, the creation of the skiing industry in the
1930s and the City’s transformation into a center for
arts and culture in the 1940s, all of which have led to
the contemporary attraction it holds for intellectuals,
outdoor enthusiasts and life-style connoisseurs.
The Early Years - Mining
Aspen is located in the Upper Roaring Fork Valley,
where people have lived for at least 5,000 years. The
Ute Indians arrived in the area around 1400 A.D. and
controlled the region until the 1870s, preventing access
to most of the valley under the 1868 Ute Reservation
Settlement Act. However, they did allow the Hayden
Survey to be completed in 1873, which was ultimately
responsible for determining the evidence of gold and
silver in the surrounding mountains.
Following the reports from the Hayden Survey, in the
summer of 1879, four prospectors from Leadville
arrived in the valley to explore the mining potential.
Quickly, they sank shafts to indicate they had mined
the land and filed claims upon their return to Leadville.
By the end of 1879 at least 35 prospectors camped
at the base of Aspen Mountain, enduring the winter
so as not to lose potential fortunes. The resulting
pressure to mine and allow settlement of the area led
to the removal of the Ute people to Utah.
Henry B. Gillespie and B. Clark Wheeler, two ambitious
men who would come to direct the growth of the
region, arrived in the mining camp in the spring of
1880. Although it was Gillespie who initiated the
efforts to create a town (which was to be called Ute
City), Wheeler was first to complete a survey, and he
gave Aspen its name. In March of 1880, B. Clark
Wheeler incorporated the Aspen Town and Land
Company with the financing of eastern capitalists.
Initially, Aspen was a typical mining camp, with
tents and crude log structures for businesses and
homes. Transportation into the area was only by way
of Taylor Pass, through Ashcroft until 1881, when
the Independence Pass Toll Road was completed.
Between 1883 and 1885, the population increased
from 500 to 3,500 people, and the town had municipal
water service, a telegraph, telephones and electricity,
thanks to what was reportedly the first commercially
operated hydroelectric plant in the United States.
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A spen H istoric o verview
View of Aspen in 1900.
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Aspen was in the thrust of a building boom, including
construction of over twenty business buildings, and in
1884, well over one hundred homes to meet a housing
shortage. Civic improvements were made and the City
Council added street signs and house numbers. The
town was platted into 30’x100’ lots and the city was
divided east-west by Center Street (now Garmisch
Street,) and north-south by Main Street. These two
thoroughfares were both 100-feet-wide, while other
streets were 75-feet. The residential districts were
generally within proximity to the trails leading to the
mines. The commercial district, originally four blocks
in size, was located at the base of Aspen Mountain.
The industry associated with the mining process
such as the mills were located on the perimeter of the
town. According to the Time’s editor, reflecting on the
character of the town, “the pretty cottages, the palatial
stores and the neat churches and public buildings,
attest to their energy, prosperity and cultivation.”
Many of Aspen’s achievements in the mid-1880s
can be attributed to an eastern capitalist, Jerome
B. Wheeler, no relationship to B. Clark Wheeler.
Among other investments, Wheeler facilitated
the development of two major sources of mining
infrastructure—a smelter to process the ore locally for
greater economic return and a railroad to connect the
town to outlying regions.
By 1886, two railroad companies were in competition
to reach Aspen first; the Denver & Rio Grande Railroad
and the Colorado Midland Railroad, which was
partially bankrolled by Jerome Wheeler. The first train
on the Rio Grande line pulled into Aspen in November
of 1887. The Colorado Midland was hindered by
bridge construction over Maroon and Castle Creeks,
but ultimately arrived in town in December 1887. The
railroad cars carried three to four thousand tons of ore
each week to be processed; the returning cars brought
valuable merchandise, including commodities and
luxury items.
As Aspen prospered, around 1888, more substantial,
brick and stone, high style buildings began to be built.
It was the custom of the day for successful
businessmen to build a city block in a unified
architectural style, using the best location for his own
business and renting out to others. The business
blocks (for example the Aspen Block, on the southwest
corner of Hyman and Galena) were symbols of the
prosperity of the town, and the individuals for whom
they were named, as well as a growing civic pride.
Two of the most important structures built during this
period were financed by Jerome B. Wheeler—the
Wheeler Opera House and the Hotel Jerome.
Most of the houses built during this time were from
designs found in pattern books, volumes of building
plans that were widely available. The majority of the
homes were wood frame, although some larger and
more elaborate houses were constructed of brick.
The miner’s cottages generally measured twenty-
eight feet by thirty feet and were divided into five main
spaces: a parlor (with bay window), sitting room,
kitchen, sleeping area and a porch. An outhouse and
sheds for livestock also would have been located on
the lot. Exterior detailing on the cottages was relatively
minimal, mostly focusing on the porch and the most
prominent window. Produced at a rate of four per day,
this family house, painted, plastered and ready for
occupancy, cost $1,000.00 to build. The 300 block of
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A view of Cooper Avenue in 1900.
A view of houses on Lake Avenue in 1910.
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E. Main Street contains examples of the pattern-style,
vernacular miner’s cottage.
Residential landscapes at this time were often
utilitarian in design, with small vegetable gardens
and few ornamental plantings. Fences were low
and transparent in nature to provide some definition
between private yards and the public right-of-way.
The planting of cottonwood rows was the dominant
landscaping feature in the residential and commercial
districts. Small irrigation ditches to promote growth
linked the tree-plantings.
In spite of fast-paced construction, by 1889 the
housing shortage continued in Aspen, especially for
miners’ families. In response, in September of 1889,
the city council chartered a company to create a
horse-drawn streetcar line. The completed system
stretched two miles, crisscrossing the town and
changing the face of Aspen by expanding its limits
beyond the walking capacity of pedestrians.
The Silver Crash - Aspen’s Quiet Years
By 1892 Aspen was the third largest city in Colorado
with 12,000 residents—only surpassed by Denver and
Leadville. Aspen did outpace Leadville as Colorado’s
leading silver producer, and housed the largest opera
house in the state and finest luxury hotel on the
Western Slope. In the spring of 1893, the financial
success of Aspen crashed when Congress repealed
the Sherman Silver Purchase Act. The “Silver Queen”
of the Rockies came to a grinding halt, as did almost
all of Colorado’s silver mines. By the end of 1893,
the mining workforce had dropped from 2,250 to
150 men. By 1900, Aspen’s total population had
dropped to 3,300 people and by 1930 had reached
a low of 700 people. The events of 1893 initiated a
period commonly referred to as the ‘’Quiet Years’,
which lasted until the 1930s. Homes were vacant,
stores empty and the grand architecture of the
commercial and residential blocks entered a long
stage of deterioration and neglect. Entire blocks were
barren without a single occupied house and buildings
stood as bare skeletons, the victims of salvaging for
materials, fire and vandalism.
During the “Quiet Years,” most people survived on
modest resources. Residents raised much of their
own food, merchants extended credit when possible
and neighbors shared with neighbors. Throughout
this extended depression numerous records indicate
an enduring pulse of optimism amongst Aspenites.
The theme of unfailing pride dominated during the
“Quiet Years.”
The major transportation services, the Midland
Railroad and the Rio Grande Railroad were also
affected by the financial crisis. The Midland line was
purchased by the Santa Fe Railroad, but the route was
abandoned by 1900 and the track was removed by
1921. The Rio Grande was more fortunate and endured
the silver crash by hauling cattle and sheep rather
than silver. By the 1930s and 1940s it once again met
market demands by hauling the building materials
and eventually passengers for the development of
Aspen as a ski resort.
Aspen’s Second Cycle-Ski Town
Snow and spectacular mountains would provide
the resources in the 1930s for Aspen to begin
development as an international ski resort. While
miners had previously used old barrel staves to slide
down the mountain after work, they never guessed
that this transportation method would be the next
boom for their remote mining town.
It was the chance meeting of a miner’s son, Tom
Flynn, with Olympic bobsled champion, Billy Fiske
in California that initiated speculation for the ski-
industry in Aspen. Fiske soon hired Andre Roch,
a celebrated mountaineer, avalanche expert and
engineer, to survey the area. Roch spent the next six
months identifying the recreational advantages of
the region. Following the survey, Fiske and capitalist
Theodore Ryan personally cleared brush off the
hillside, creating the first alpine slope near Aspen.The Marolt Ranch in 1920, with the defunct Holden Lixiviation
Plant (a silver processor) in the background.
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Roch developed a downhill race course. Originally
called “Roch Run Trail” or “the Roch”, only a section
of the original course remains today. Roch believed
that by creating a race course, Aspen would receive
more publicity, thereby development of the mountain
would be accomplished more quickly. It was a great
success, attracting not only top skiers, but visionary
capitalists.
In 1938, Roch’s served as the site for the Rocky
Mountain Ski Association Championship and by
1941, the Aspen Ski Club hosted the U.S. World
Alpine Championships. World War II interrupted the
development of Aspen skiing; but troops in training
at the 87th Mountain Infantry and later the 10th
Mountain Division would come to test their skills on
the weekends. After the war, many of these same
people came back to settle in Aspen and continue
the momentum of developing its skiing potential.
By 1950 Aspen was internationally famous for its
terrain, World Cup Ski events and pioneering ski-
industry technology. Lift capacity continued to
expand at Aspen and new ski areas were developed.
In 1957, Aspen Highlands opened, to be followed by
Buttermilk a year later. The significant addition of the
Snowmass ski area in 1967 firmly established Aspen
as an international skiing destination. By 1986, Aspen
installed the world’s longest, single-stage vertical
rise gondola—the Silver Queen. Aspen continues to
maintain its position as an international ski resort,
attracting the world’s top skiing competitors and
most celebrated ski events.
Skiing also changed the architectural character of
Aspen. Lodges were built in the chalet style familiar
to their European owners. To enhance the alpine
experience for tourists, landscaping trends attempted
to bring the mountain environment into town.
Spruce trees and other conifers were planted along
streetscapes and throughout the commercial and
residential districts.
Aspen’s Cultural Renaissance - The Aspen Idea
Investment capital began to flow into Aspen as
influential people such as Elizabeth and Walter
Paepcke promoted the town. The Paepckes were
Chicago industrialists with grand visions. Walter
Paepcke dreamed of a community “of peace with
opportunities for a man’s complete life...where he
can earn a living, profit by healthy, physical recreation,
with facilities at hand for his enjoyment of art, music
and education.” He created the Goethe Bicentennial
Convocation in 1949, which attracted the world’s
foremost artists, writers, musicians and celebrated
humanitarians. The success of this event led to
the creation of the Aspen Institute, Aspen Center
for Physics, Aspen Music Festival and School,
and numerous other world class conferences and
events enjoyed in Aspen today. The International
Design Conference, founded in 1950 left an indelible
impression upon the architectural characteristics
Lift One, 1950.
Aspen Institute, 1965.
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of Aspen and how the Aspen community promotes
innovative design. Examples of private residences
and civic structures influenced by the Modernist
movement can be found throughout the city.
Present Day Aspen - International Resort for
the Mind and Body
Aspen lures people today with world-class
accommodations, outdoor recreation opportunities,
artistic venues and educational forums. Its setting,
unique architecture and sense of history provide a
backdrop whereby the Aspen community can provide
the best of both worlds— charm and natural beauty
with cosmopolitan entertainment and flare.
The Elks Building, 2015.
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Note: Dates indicated describe the approximate
period covered by a particular building style within
Aspen.
Architectural Styles in Aspen
The City of Aspen contains a wide variety of building
types and architectural styles that reflect its
evolution, many of which have historic significance.
This rich architectural heritage enhances the City and
contributes to its strong “sense of place.”
The following is a brief overview of the most frequently
recognized styles found in Aspen. This survey of
building types and styles reflects changing building
technologies, tastes of the times, and the distinct
Aspen context.
Pioneer
Circa 1879-1893, Residential
These buildings were generally constructed of round
logs, hewn logs, or log slabs considered to be mill-
waste, and built as basic shelter for early Aspen
settlers. Later examples copied this style. The log
members were laid on alternating tiers, implementing
a variety of notching techniques for joinery. The
details of the log connections and the character of
the log cuts themselves are important features. The
spaces between the logs were filled with “chinking”
consisting of a mixture of animal hair, clay, straw and
other natural materials. The roofs were constructed of
readily available material, including canvas, wooden
shingles, and sheet metal. In Aspen, some of these
log structures were later updated and covered with
milled wooden siding and details.
Characteristics:
•Log construction.
•Hip or gable roof.
•Rough-sawn wood trim.
A Pioneer house at 205 S. Third, constructed in 1885, or earlier
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False-Front Store Front
Circa 1880-1893, Commercial
Relatively few examples of false-front buildings
survive. These structures are from the early settlement
phase when wood was the primary construction
material. The front created a facade that made a
building appear larger and taller than it actually
was, masking a gabled roofline. Cornice details and
kickplate elements below the storefront windows also
were created from wood.
Characteristics:
•Gable roof concealed behind false front.
•Recessed entry.
•Large glass display windows.
•Simple bracketed cornices.
•Painted wood lap siding.
•Kickplate below display window.
•Transom above display window.
•Wood doors and windows.
Carpenter Gothic
Circa 1880-1893, Residential
This style is characterized by wooden interpretations
of Gothic masonry structures, with an emphasis upon
verticality and picturesque composition. Jig-saw cut
trim elements were popular but straight lines and
simple geometric forms provided the framework for
more ornamental attachments. These ornamental
details and the overall vertical form of this style are
important features that should be preserved. All-
white color schemes were popular, with accent colors
only appearing on shutters.
Characteristics:
•Steeply pitched roof.
•Cross gable roof plan or side gable roof plan with
central cross gable over the door.
•Clapboard siding.
•Decorative barge board along eaves of main
gables and dormers.
•Two-over-two, double-hung sash windows.
•Bay windows and lancet windows.
•Elaborate porch railings, square posts, cut-out
boards.
False front structure at 310 E. Main, constructed in the 1890s.
A Carpenter Gothic house at 302 East Hopkins, constructed in
1883.
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Vernacular L-Type or “Miner’s
Cottage”
Circa 1880-1893, Residential
The term “vernacular” refers to building traditions
that reflect local taste, customs and materials. The
vernacular houses of Aspen are similar to those
throughout other Colorado mining towns—these
houses were designed for utilitarian purposes with
minimal attempts to copy a prescribed style. Typically,
decorative elements were applied to cottages with
steep roofs, wooden siding, vertical sash windows and
front porches. Some homes received more ornament
than others, often influenced by Queen Anne or
Gothic Revival designs, usually around windows and
doors and at porches and gable ends. In plan, these
cottages were L-type, gable end, or side gable. Often
shed additions were added.
The L-type houses have two wings with intersecting
gable roofs that form a letter “L” in plan. Very often an
attached porch runs along the street-facing facade.
Most of these houses are 1- story, but 1-1/2 and
2-story versions also exist. This is the most common
historic resource type remaining in Aspen.
Characteristics:
•Overall, simple building forms.
•1-story, covered porch, usually at the intersection
of the two wings.
•Projecting bay windows.
•Wood clapboard siding.
•Shingle roof.
•Two front doors, a social custom.
Side Gable
Circa 1880-1893, Residential
This house style has a ridgeline that runs parallel to
the street. Often a porch runs the width of the house.
Details are similar to other gable cottage plans.
Characteristics:
•Full-width, one-story porch.
•Decorative elements focused on the porch area.
•Porch projects forward from the front wall plane.
•Painted wood lap siding.
•Wood trim around windows and doors.
A Vernacular L-type house at 205 S. Spring, constructed in
1887.
A side gable house at 117 N. Sixth, constructed in 1885.
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Gable-End
Circa 1880-1893, Residential
This house type has a simple, rectangular shape with
a gable roof with the ridge running perpendicular to
the street. Most have a porch on the gable-end. Most
are wood sided. Most are 1 - 1-1/2 story and a few
are 2-story.
Characteristics:
•Bay-windows .
•Full width or inset 1-story porch, with hip or gable
roof.
•Decorative shingles in gable-end.
•Gable ornaments, including brackets and barge
boards.
•Overall, modest character.
•Porch may project forward or be inset into the
front wall plane.
•Two front doors, a social custom.
Italianate
Circa 1880-1893, Residential and Commercial
The Italianate style was introduced by Andrew Jackson
Downing in his 1850 publication, The Architecture
of Country Houses. He extolled the virtues of the
Gothic Revival, but also offered the “villa,” a version
based on Italian country houses that veered more
toward classicism and did not have the religious
overtones of the Gothic Revival. Cornices with large
brackets appeared on porches and bay windows. Flat,
ornamental arches capped most windows and doors.
Characteristics:
•Rectangular, square, with a side-passage plan, or
cross-gable.
•Brick, wood clapboard and stucco.
•Double-hung, narrow windows, often with round
arch heads.
•Window panes are either one-over-one or two-
over-two.
•Protruding sills.
•Ornate treatment of the eaves, including the use
of brackets, modillions and dentil courses.
•Low-pitched, hipped roof.
•Bay windows, often rectangular.
•Quoins, or decorative blocks, at corners.
•Metal cresting along roof ridges.
•Transom over entry, often curved.
An gable end house at 612 W. Main, constructed in 1888.
An Italianate house at 201 E. Hyman, constructed in 1883.
The Wheeler Opera House at 320 E. Hyman is an example of an
Italianate commercial structure, constructed in 1889.
•Ornate treatment of porch with turned columns,
posts and bargeboard ornament.
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Dutch Colonial Revival
Circa 1880-1893, Residential
The most distinguishing feature of this style is the
gambrel roof. The details, such as the window pattern,
porches and materials are closely associated with the
Shingle and Queen Anne styles.
Characteristics:
•Gambrel roof; both side-passage and front-facing
variations can be found.
•Single gable end.
•One story.
•Prominent front porch, with classically-detailed
porch supports and plain balustrades.
•Double-hung sash windows, with either single
panes or multiple panes in the upper light.
•Lunette windows in the upper gable.
•Large, single pane windows with a fixed transom
on the first story.
Queen Anne
Circa 1880-1893, Residential
In the United States, Queen Anne developed from the
desire to establish a national style. This style includes
decorative wall surface patterns, framed in strap-
work, polychrome color schemes, and steeply pitched
rooflines. Typically, the buildings are 1 - 2-stories in
height. Preserving the ornamental details and the
original materials of this style are high priorities.
Characteristics:
•Irregular, asymmetrical massing.
•Forward extension of wall planes; towers and
triangular sections.
•Decorative shingles.
•Spindlework porch supports with lace-like
brackets.
•Windows with leaded or stained glass.
•Patterned window panes.
•Bay windows.
•Corbelled brick chimneys.
A Dutch Colonial Revival house at 611 West Main, constructed
in 1886.
A Queen Anne house at 128 E. Main, constructed circa 1893.
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Second Empire
Circa 1880-1893, Residential
The Second Empire refers to the reign of Louis
Napoleon, the grand-nephew of Napoleon Bonaparte,
who ruled France from 1852 to 1870. In both France
and America, the Second Empire style coincided
with a period of prosperity and materialism, and was
associated with urbanity and a cosmopolitan society.
The style is characterized by its distinctive mansard
roof, often containing windows on the steep lower
slope. The complex massing and arrangement of
towers is unified through decorative cornices similar
to those of the Italianate style.
Characteristics:
• Steeply pitched, mansard roof.
• Roof can be either straight or concave, and is
interrupted by dormers.
• Complex massing forms .
• Brick, stucco or wood clapboard.
• Wrought-iron ornament, such as cresting on roof
or heavy, ornate fencing.
• Wide eaves, often with modillions.
• Corbelled chimney.
• Heavily molded cornices and window trim.
Industrial
Circa 1880-1893, Commercial, Public
The Industrial style represents an age when the
production of goods was an overriding goal. This
style was sometimes employed for utilitarian public
buildings, and featured large, open interior spaces,
made possible by a heavy wood truss system.
Characteristics:
• Large rectangular forms.
• Masonry construction.
• Large interior spaces.
• Smaller, vertically proportioned windows.
• Masonry cornice supported on corbels.
A Second Empire house at 442 W. Bleeker, constructed in 1885.
Aspen City Hall, originally an Armory, at 130 South Galena,
constructed in 1891.
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Victorian-Era Commercial Building
Circa 1880-1893, Commercial
The commercial storefront of the late 19th and early
20th centuries is the most common type of building
found today in most historic commercial districts
throughout the country. Usually one to four stories
in height, these buildings are divided into two distinct
bands. The first floor is more commonly transparent,
so goods can be displayed, while the second story
has smaller windows and is usually reserved for a
residential or office space. The majority of these
buildings in Aspen were constructed between 1888
and 1893.
As this type evolved towards the turn-of-the century,
so too did the amount of ornamentation and high-
style influences. Cornice and midbelt moldings
became more prominent, more elaborate window
and door openings were used and much of the
facade was covered with varying degrees of applied
ornamentation. Italianate details were popular. With
the introduction of cast-iron, the weight of second and
third stories of these Victorian commercial structures
was carried over larger expanses of glass on the first
floor.
Characteristics:
• Cast-iron supported or wood post storefronts.
• Large display windows on the first-floor usually
framed in wood, but sometimes metal.
• Transom lights above display windows.
• Kickplate below display windows.
• Recessed entry.
• Wood double doors.
• Tall second story windows with wood frames.
• Decorative cornice at top.
• Masonry walls.
• Varying degrees of ornamentation.
• Corner entry.
A Victorian era commercial building at 419 E. Hyman,
constructed in 1889.
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The Collins Block, located at 204 South Mill Street, constructed
in 1891-1893.
Neo-Classical
Circa 1880-1893, Commercial
The Neoclassical movement is an American
phenomenon that began with the 1893 Colombian
Exposition in Chicago. Greek Revival precedents
were most commonly used, but with more variety
in composition and detail. In Aspen, popular
neoclassical details were simple Doric columns,
triangular pediments and large cornices with rows
of dentil moldings. Other classical orders, including
Corinthian and Ionic, sometimes are used as well.
These appeared on both residential and commercial
buildings.
Characteristics:
• Free-standing columns, usually Doric order.
• Cornice with dentil moldings.
• Triangular pediment, sometimes supported on
classical columns.
Romanesque Revival
Circa 1880-1893, Commercial and Public
Promoted by the prominent Boston architect,
Henry Hobson Richardson, the Romanesque, or
Richardsonian Romanesque style was commonly
used for large public buildings during the 1880s—
following suit with Richardson’s Trinity Church in
Boston. Romanesque structures were always of
masonry construction. Rounded stone arches were
typical details, as were carved stone columns with
Corinthian capitals, which feature an acanthus leaf
pattern. Attached stone pilasters, or piers also were
common.
Characteristics:
• Asymmetrical facades.
• Masonry walls, usually with rough-faced, squared
stonework.
• Most have towers with conical roofs.
• Round-topped arches over windows, porch
supports, or entrance.
• Deeply recessed openings.
• Decorative colonnettes around windows.
• Decorative floral patterns on column capitals and
wall surfaces.
• Wood frames for doors and windows.
The Aspen Community Church, an example of the Romanesque
Revival style, constructed at 200 E. Bleeker in 1890.
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Rustic architecture at 300 W. Main, constructed in 1944.
Rustic Architecture
Circa 1900-present, Residential, Commercial, Public
Popularized by the designs of the National Park
Service for its institutional buildings, these structures
were designed to blend with the environment and
were constructed of native building materials. An
emphasis upon simplicity, hand craftsmanship and
the natural environment made this a popular style
for vacation homes, hunting lodges, dude ranches
and tourist facilities. In Aspen, these appear similar
to Pioneer Houses, but usually include larger timber
elements and emphasize more craftsmanship in
details.
Characteristics:
•Hand built out of locally available materials, using
limited tools.
•Single story or 1 1/2 story.
•Low pitched gable roof.
•Simple rectangular footprint, with smaller
addictive elements.
•Small porch or entry feature.
•True log construction with overlapping log
ends, coped and stacked, with chinking to infill
irregularities between the logs.
•Rough sawn board and batten siding.
•Stone at the base or in the fireplace and chimney.
•Small window openings, spare and usually
horizontally proportioned with wood trim.
•Minimal detail and decoration.
The Bell Tower, originally built as a WPA project in 1930 and
later substantially reconstructed, is located at Paepke Park and
is an example of Rustic architecture.
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International style residence at 301 Lake, constructed in 1972.
Bauhaus/International Style
Circa 1928-1960, Residential, Commercial, Public
The use of the words “international style” refers to the
title of the exhibit promoted by the Museum of Modern
Art in New York City in 1931 which presented the
work of forty architects from fifteen countries. It has
become synonymous with modern styles and post-
World War II architecture that emphasized simple
rectilinear forms that expressed internal functions.
New materials and construction techniques also
were used. In Aspen, some variations emphasized
techniques and materials from elsewhere, while
others adapted the International Style to local
materials and building methods. Several of the
International Style buildings in Aspen were designed
by Herbert Bayer, a noted artist and designer from the
Bauhaus school who had a significant influence on
postwar architectural development in Aspen.
Characteristics:
•Simple geometric forms, both in plan and
elevation.
•Flat roofs, usually single story.
•Proportions are long and low, horizontal lines are
emphasized.
•Asymmetrical arrangement of elements.
•Windows are treated as slots in the wall surface,
either vertically or horizontally, or glazing appears
as a curtain wall.
•Detailing is reduced to the composition of
elements rather than decorative effects.
•Materials are generally manufactured and
standardized, surfaces are smooth, with minimal
or no detail at window jambs, grade, and roof
edge.
•Entry is usually marked by a void in the wall, a
cantilevered screen element, or other architectural
clue that directs one into the composition.
•Buildings are connected to nature through the use
of courtyards, wall elements that extend into the
landscape, and areas of glazing that allow a visual
connection to the natural environment.
•Schemes are monochromatic, using neutral
colors. Primary colors are used for accents.
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City of Aspen • Historic Preservation Design Guidelines • 31
HIstorIc overvIew
Chalet
Circa 1945-1960s, Residential and Commercial
This style is reminiscent of alpine architecture in
Europe and was popular for early American ski resort
towns, including Aspen. Large balconies and shallow
roofs with wide eaves are identifying features. Wood
trim often reflected a jig-saw cutout design, especially
on balustrades and gable ornaments. Stucco was
often combined with wood siding. Occasionally,
mountain scenes were painted on the stucco. The
style primarily used for hotels and residences.
Characteristics:
•Large, singular roof form, generally low in slope.
•Deep overhangs with the structure of the roof
expressed on the underside.
•Eaves and rakes decorated with cutouts and
fretwork bargeboards.
•Continuous porch or balcony running the length
of the primary side.
•Decorative elements such as balustrades with
cut out shapes (hearts, edelweiss, snowflakes,
nature theme).
•Rectangular footprint.
•Stucco ground floor with minimal openings and
wood lintels.
•Slider and casement windows, horizontally
proportioned and used sparingly.
•Decorative shutters or flowerboxes.
•Colors are restricted to white for the stucco
base and dark brown wood walls, eaves,
and balustrades. Bright colors are used
sparingly for accents and decorative elements.
Mountain Chalet Style at 312 W. Hyman, constructed in 1956.
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32 • City of Aspen • Historic Preservation Design Guidelines
HIstorIc overvIew
A Modern Chalet Style home at 120 Red Mountain Road,
constructed in 1962.
A Pan Abode located at 630 W. Main, constructed 1965.
Log Kit/Pan Abode Buildings
Circa 1950s to 1970, Residential and Commercial
Pan Abode is a brand name for log kit houses
available beginning in 1952. These buildings were also
manufactured by other companies as early as 1948.
The logs were milled, tongue and groove and came
pre-cut and notched for easy assembly. The system
was popular in Aspen for ski lodges and modest
homes. They were quick to build (a plus in Aspen’s
limited construction season) and inexpensive.
Characteristics:
•Tongue and groove cedar log construction.
•Overlapping notches at corners.
•Wood framed, multi-light picture window.
•Low-pitched roof, usually gabled but occasionally
shed.
•Deep overhanging eaves.
•Recessed entrance with rounded or squared
corners.
•Natural, stained wood.
•Simple, rectilinear footprint usually one story.
Modern Chalet
Circa 1950s-1960s, Residential
A distinctive postwar housing type in Aspen is
locally termed a Modern Chalet. With its moderately
pitched gable roof oriented to the front, it recalls
traditional chalets associated with ski country, but
in its expansive glass and minimal decoration, it also
seems classically modernist. For the most part, the
sizable window walls on these buildings are oriented
to Aspen Mountain.
Characteristics:
•Rectilinear footprint, classic chalet orientation
with gable end to the street and/or mountain view.
•Broad gabled facade organized in rectilinear
solid or glass panels, generally in a tripartite
organization.
•Low to moderate pitched roof, often based on a
3:12 ratio.
•Roof eave comes down to a low plate height at
the upper level.
•Deep eave overhang, may have exposed roof
beams.
•Glass in gable ends extending to the eaves.
•Large central glazed areas is flanked by brick or
stone piers.
•Minimal decoration.
•Balcony on front facade.
•Entry door recessed or on side elevation.
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City of Aspen • Historic Preservation Design Guidelines • 33
HIstorIc overvIew
This Wrightian style building is located at 720 E. Hyman, and
was constructed in 1976.
Wrightian/Organic
Circa 1945-Early 1970s, Residential, Commercial,
Public
The Wrightian style was developed by the architect
Frank Lloyd Wright. Several buildings in Aspen were
designed by architects who studied under Frank
Lloyd Wright.
Characteristics:
•Low horizontal proportions, flat or low pitched hip
roofs.
•Deep roof overhangs that create broad shadow
lines across the facade, glazing is usually
concentrated in these areas.
•Materials are usually natural and hand-worked,
such as rough-sawn wood timbers and brick,
brick is generally used as a base material, wall
infill, or in an anchoring fireplace element.
•Wood structural systems tend more toward heavy
timber or post-and-beam rather than typical stud
framing.
•Structural members and construction methods
are usually expressed in the building.
•Roof structure is often expressed below the roof
sheathing.
•Glass is used as an infill material which expresses
a void or a structural system, or it is used to
accentuate the surface of a wall through pattern
or repetition.
•No trim isolating the glazing from the wall plane,
window openings are trimmed out to match
adjacent structural members in a wood context,
brick openings tend to be deeply set with no trim
other than the brick return.
•Structures are related to the environment through
battered foundation walls, cantilevered floors
and/or porches, clear areas of glazing that create
visual connections between inside and outside,
and the effect of the roof plane hovering over the
ground.
•Decoration stems from the detailing of the
primary materials and the construction technique,
no applied decorative elements are used.
•Colors are usually related to the natural colors
of materials (natural brick, dark stained wood,
white stucco), accent colors are used minimally
and mainly to accentuate horizontal lines of the
structure.
This Wrightian residence is located at 835 W. Main, and was
constructed in 1947.
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D esign g uidelines :c ontext
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36 • City of Aspen • Historic Preservation Design Guidelines
cHapter 1: sIte plannIng & landscape desIgn
c HA pter 1: s ite p l A nning & l A ndsc A pe d esign
Background
The character of a historic structure is greatly
influenced by the surrounding framework of streets
and public spaces, the physical characteristics of the
specific site, and the way in which the historic resource
is situated on the lot. It is important to analyze the
context of a property before developing a strategy for
treatment and/or alteration. Analysis should begin
with a study of the overall development pattern of
the neighborhood or district. The defining elements
of the site need to be identified, and the placement
of the historic resource reviewed for its consistency
or deviation from the context of the neighborhood or
district. How structures occupy their site, in terms of
alignment, orientation, and spacing creates much of
the context of a neighborhood. This context, along
with right-of-way treatment, sidewalks, pedestrian
and vehicular access, fences, natural features, alley
relationship, landscaping and other site features all
combine to define Aspen’s historic character.
In the original Aspen townsite, the consistency of site
development reflects a specific and identifiable time
period. Some neighborhoods located outside of the
formal townsite grid were planned much later and
reflect a less formal pattern of development. HPC’s
intent is that any project acknowledges the history
of the surrounding area and uses the strongest and
most common features as a framework for proposed
development.
In addition to architectural landmarks, Aspen has
significant cultural and historic landscapes that
represent early development patterns. Included in
these private and public landscapes are: cemeteries,
parks, campuses, public art, alleys, street right of
ways, waterways, and similar public features. These
landscapes are integral to the historic pattern of the
community and should be preserved.
How to Start
When beginning a project, the applicant should follow
these steps:
•Document the existing site conditions, including
existing plant material, natural features, historic
artifacts, and configuration of the site.
•Note neighborhood development patterns
including existing and historic street and alley
conditions, setbacks, and alley development.
•Determine whether the existing context supports
or detracts from the historic resource and
incorporate findings into the design process.
•Retain historic site features and incorporate
important existing and historic development
patterns into the site.
Policy: Historic landscapes, landscape elements,
and landscape patterns should be preserved.
Additions and/or changes to the landscape
should be compatible with the associated
historic resource and the historic context of the
neighborhood or district in which the project is
located.
Note: A permit is required for modifications
within the publically owned right-of-way,
including planting strips, sidewalks and irrigation
ditches. This permit is issued by the Engineering
Department in consultation with other City
agencies. In general, the right-of-way within a
given neighborhood should have a consistent
design character. Right-of-ways should not be
altered in a manner that makes them appear to
be an extension of the adjacent private property.
The Municipal Code includes detailed information
about the City’s regulations affecting trees on
public and private property.
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City of Aspen • Historic Preservation Design Guidelines • 37
cHapter 1: sIte plannIng & landscape desIgn
Neighborhood and District Patterns
Maintaining significant development patterns in
Aspen’s neighborhoods is important. Intentionally
siting buildings to highlight historic development
patterns reflects the evolution of Aspen’s development.
Resources which are helpful in studying development
patterns include Victorian era fire insurance maps
(Sanborn Maps), the 1896 Willit’s Map, the 1893
Bird’s Eye View of town, subdivision maps, aerial
photography, and GIS mapping. These are found
in the Community Development Department or the
Historical Society. GIS maps can be found online at
aspenpitkin.com and Sanborn maps are online at
www.cudl.colorado.edu.
Within the historic townsite, the road layout is a grid.
The neighborhoods and structures were organized in
an orthogonal pattern, regardless of topography, with
building façades parallel to the street. Main Street is
the widest boulevard dividing Aspen north and south.
Garmisch Street, formerly Center Street, divides the
townsite east and west. In the west part of town,
historic irrigation ditches are found alongside many
streets.
Within the original townsite, some Post-World War II
buildings were set at an angle on the lot as a reflection
of a different design philosophy – for example, many
chalets are oriented to face Aspen Mountain. In later
subdivisions, the grid is generally absent: streets are
curvilinear and lots are irregular. It may require careful
study to discern consistent or original development
patterns remaining in these areas due to intense
redevelopment. Consult with a landscape architect
early in the conceptual process.
1.1 All projects shall respect the historic
development pattern or context of the block,
neighborhood or district.
•Building footprint and location should reinforce
the traditional patterns of the neighborhood.
•Allow for some porosity on a site. In a residential
project, setback to setback development is
typically uncharacteristic of the historic context.
Do not design a project which leaves no useful
open space visible from the street.
Streets, Alleys, & Ditches
Alleys are an important feature of the historic townsite
and have traditionally been used for utilitarian
functions. Today, this is an appropriate location
for cars, storage, service areas, and in some cases,
secondary residential units or small businesses.
Historic photograph of Aspen’s west end neighborhood.
This historic structure is easily viewed from the street and is
surrounded by a large open yard.
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38 • City of Aspen • Historic Preservation Design Guidelines
Though alterations to streets, alleys, and ditches are
not generally within the HPC’s purview, development
which removes a platted street or alley, or overplants a
ditch, is discouraged. Ditches should be simple water
channels planted with sod banks that do not include
flower beds, hardscapes, or bridges that change the
simplicity of the feature.
1.2 Preserve the system and character of
historic streets, alleys, and ditches.
When HPC input is requested, the following bullet
points may be applicable.
•Retain and preserve the variety and character
found in historic alleys, including retaining historic
ancillary buildings or constructing new ones.
•Retain and preserve the simple character of
historic ditches. Do not plant flowers or add
landscape.
•Abandoning or re-routing a street in a historic
area is generally discouraged.
•Consider the value of unpaved alleys in residential
areas.
•Opening a platted right of way which was
abandoned or never graded may be encouraged
on a case by case basis.
Driveways & Parking
Typical transportation in the 19th Century included
horses and wagons that were housed in the alleys or
on side streets. As cars became more common after
World War II, some development was automobile
oriented and included driveways accessed from
the primary street. Many Post-War residences
incorporated this auto-centric trend with carports
and these examples should be preserved. Generally
though, in an effort to minimize the visual impact of
vehicles, and meet current pedestrian safety goals,
vehicular access should now be accommodated at
the alley where possible.
1.3 Remove driveways or parking areas
accessed directly from the street if they were
not part of the original development of the site.
•Do not introduce new curb cuts on streets.
•Non-historic driveways accessed from the street
should be removed if they can be relocated to the
alley.
Where a historic driveway is accessed from a street, minimize
the visual impacts by limiting paving.
This Herbert Bayer designed residence, built in 1963, features
a streetfacing carport.
cHapter 1: sIte plannIng & landscape desIgn
A ditch in the West End neighborhood.
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City of Aspen • Historic Preservation Design Guidelines • 39
cHapter 1: sIte plannIng & landscape desIgn
1.4 Design a new driveway or improve an
existing driveway in a manner that minimizes
its visual impact.
•If an alley exists at the site, the new driveway must
be located off it.
•Tracks, gravel, light grey concrete with minimal
seams, or similar materials are appropriate for
driveways on Aspen Victorian properties.
Yards, Walkways, and Patios
Key landscape features include setbacks, public
space and private space, the arrangement of trees,
shrubbery and hedges, species of vegetation, natural
features, walkways and patios, site furnishings, site
lighting, fences, vehicular and pedestrian access, and
walls.
Aspen Victorian Properties
Commercial zone districts allow lot line to lot line
development with minimal setbacks if any. As such,
most commercial properties do not contain on-site
walkways and patios. This alignment of structures
contributes to a sense of visual continuity and vitality
for 19th Century resources in the Commercial Core
Historic District.
In 19th century residential settings, a “hierarchy” of
open space exists along the street. Access from the
public street to private residences was commonly
achieved with a modest walkway. These walkways
were typically narrow in width, made of simple,
indigenous materials, and ran perpendicular from
the street to the entry or porch. Typical residential
neighborhoods located in the original townsite had a
relatively consistent front yard setback. Open lawns
were common. Side and rear yard setback patterns
created distinctive patterns and contributed to the
overall open space and rhythm of a neighborhood.
Rear yard setbacks have traditionally been fairly
minimal
AspenModern Properties
Post-war development oftentimes reflects a
deliberate effort to bring the outside indoors or to
contrast a natural, wild landscape with a minimalist,
stark building. Many Post-War buildings incorporated
patios, built in planters, deep overhanging eaves, wide
steps, and other types of design elements to define the
landscape as part of the architecture of the building.
These features are integral to the design tenets of
Post-War architecture and should be preserved.
An elevated front patio was part of the original design for
this AspenModern landmark in the Commercial Core Historic
District.
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40 • City of Aspen • Historic Preservation Design Guidelines
1.5 Maintain the historic hierarchy of spaces.
•Reflect the established progression of public to
private spaces from the public sidewalk to a semi-
public walkway, to a semi private entry feature, to
private spaces.
1.6 Provide a simple walkway running
perpendicular from the street to the front entry
on residential projects.
•Meandering walkways are not allowed, except
where it is needed to avoid a tree or is typical of
the period of significance.
•Use paving materials that are similar to those
used historically for the building style and install
them in the manner that they would have been
used historically. For example on an Aspen
Victorian landmark set flagstone pavers in sand,
rather than in concrete. Light grey concrete, brick
or red sandstone are appropriate private walkway
materials for most landmarks.
•The width of a new entry sidewalk should
generally be three feet or less for residential
properties. A wider sidewalk may be appropriate
for an AspenModern property.
1.7 Provide positive open space within a
project site.
•Ensure that open space on site is meaningful and
consolidated into a few large spaces rather than
many small unusable areas.
•Open space should be designed to support and
complement the historic building.
1.8 Consider stormwater quality needs early in
the design process.
•When included in the initial planning for a project,
stormwater quality facilities can be better
integrated into the proposal. All landscape plans
presented for HPC review must include at least
a preliminary representation of the stormwater
design. A more detailed design must be reviewed
and approved by Planning and Engineering prior
to building permit submittal.
•Site designs and stormwater management should
provide positive drainage away from the historic
landmark, preserve the use of natural drainage
and treatment systems of the site, reduce the
generation of additional stormwater runoff, and
increase infiltration into the ground. Stormwater
facilities and conveyances located in front of a
landmark should have minimal visual impact
The historic hierarchy of spaces from public to semi-public to
private.
A flagstone walkway suits the character of this 1956 Pan
Abode home.
cHapter 1: sIte plannIng & landscape desIgn
A Victorian era walkway in Aspen.
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City of Aspen • Historic Preservation Design Guidelines • 41
when viewed from the public right of way.
•Refer to City Engineering for additional guidance
and requirements.
1.9 Landscape development on AspenModern
landmarks shall be addressed on a case by
case basis.
1.10 Built-in furnishings, such as water
features, fire pits, grills, and hot tubs, that
could interfere with or block views of historic
structures are inappropriate.
•Site furnishings that are added to the historic
property should not be intrusive or degrade the
integrity of the neighborhood patterns, site, or
existing historic landscape.
•Consolidating and screening these elements is
preferred.
Softscape Features & Plants
While most historic plant materials on private property
have been replaced over time, some specimens
do survive, particularly in residential settings. 19th
Century photographs indicate that front yards were
typically mowed grass and a mix of cottonwood trees,
lilacs, sweet peas, flowering vines, and yellow shrub-
roses. Back yards were often dirt to accomodate
animals and livestock.
In later periods, yard designs evolved - a Rustic Style
building may have a more natural, less manicured
character with informal planting of native trees, shrubs
and flowers and prominent placement of spruces
near the entry. Always refer to historic photos of the
site when available to guide landscape design.
While HPC may not have the opportunity to review
landscape alterations that do not occur as part of a
development project, the following guidelines apply to
all activity on historic sites and will be enforced when
necessary. Permits are required for site disturbances
great than 200 square feet. Refer to the Engineering
page on the city website aspenpitkin.com for updated
information.
1.11 Preserve and maintain historically
significant landscaping on site, particularly
landmark trees and shrubs.
•Retaining historic planting beds and landscape
features is encouraged.
•Protect historically significant vegetation during
construction to avoid damage. Removal of
A simple, albeit contemporary, walkway may be acceptable for
a large, ornate Victorian.
Historic cottonwood trees surround this corner lot.
cHapter 1: sIte plannIng & landscape desIgn
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42 • City of Aspen • Historic Preservation Design Guidelines
damaged, aged, or diseased trees must be
approved by the Parks Department.
•If a significant tree must be removed, replace it
with the same or similar species in coordination
with the Parks Department.
•The removal of non-historic planting schemes is
encouraged.
•Consider restoring the original landscape if
information is available, including original plant
materials.
1.12 Provide an appropriate context for historic
structures. See diagram.
•Simplicity and restraint are required. Do not
overplant a site, or install a landscape which is
overtextured or overly complex in relationship to
the historic resource, particularly in Zone A. In
Zone A, new planting shall be species that were
used historically or species of similar attributes.
•In areas immediately adjacent to the landmark,
Zone A and Zone B, plants up 42” in height, sod,
and low shrubs are often appropriate.
•Contemporary planting, walls and other features
are not appropriate in Zone A. A more contemporary
landscape may surround new development or be
located in the rear of the property, in Zone C.
•Do not cover areas which were historically
unpaved with hard surfaces, except for a limited
patio where appropriate.
•Where residential structures are being adapted to
commercial use, proposals to alter the landscape
will be considered on a case-by-case basis. The
residential nature of the building must be honored.
•In the case of a historic landmark lot split, careful
consideration should be given so as not to over
plant either property, or remove all evidence of
the landscape characteristics from before the
property was divided.
•Contemporary landscapes that highlight an
AspenModern architectural style are encouraged.
1.13 Additions of plant material to the
landscape that could interfere with or block
views of historic structures are inappropriate.
•Low plantings and ground covers are preferred.
•Do not place trees, shrubs, or hedgerows in
locations that will obscure, damage, or block
significant architectural features or views to the
building. Hedgerows are not allowed as fences.
A small conifer planted in front of a historic structure can grow
beyond expectations and completely block the building.
•Consider mature canopy size when planting new
trees adjacent to historic resources. Planting trees
too close to a landmark may result in building
deteriorate or blocked views and is inappropriate.
•Climbing vines can damage historic structures and
are not allowed.
cHapter 1: sIte plannIng & landscape desIgn
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City of Aspen • Historic Preservation Design Guidelines • 43
cHapter1: sIte plannIng & landscape desIgn
Zone A
most signicant
Zone B
moderately signicant
Zone C
unrestricted
Historic Resource
Non-historic
addition
NOTE: Zones of signi -
cance are approximate and
deviations may be deemed
appropriate by the HPC.
Zone C may include
secondary historic resourc-
es such as a historic shed
or outbuilding. When this
occurs, the allowances in
Zone B shall apply to the
areas around the historic
shed or outbuilding.
FRONT
REAR
Historic
Resource
Non-historic Addition INTERIOR LOT106
44 • City of Aspen • Historic Preservation Design Guidelines
cHapter 1: sIte plannIng and landscape desIgn
Zone A
most signicant
Zone B
moderately signicant
Zone C
unrestricted
Historic Resource
Non-historic
addition
NOTE: Zones of signi -
cance are approximate and
deviations may be deemed
appropriate by the HPC.
Zone C may include
secondary historic resourc-
es such as a historic shed
or outbuilding. When this
occurs, the allowances in
Zone B shall apply to the
areas around the historic
shed or outbuilding.
STREET
ALLEY
Historic
Resource
Non-historic Addition
STREET
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City of Aspen • Historic Preservation Design Guidelines • 45
Site Lighting
Traditionally, outdoor lighting on 19th century sites
was minimal or non-existent. While electricity was
available in Aspen in the late 1880s, based on available
historic photographs, exterior lights, including porch
lights, were not commonly found. To maintain historic
character, all outdoor lighting must be minimized.
Landscape lighting on AspenModern properties
varies based on architectural style and time period of
development.
For additional information, see the City’s Lighting
Standards.
1.14 Minimize the visual impacts of landscape
lighting.
•Landscape and pathway lighting is not permitted
in Zone A (refer to diagram) on Aspen Victorian
properties unless an exception is approved by
HPC based on safety considerations.
•Landscape, driveway, and pathway lighting on
AspenModern properties is addressed on a case-
by-case basis.
•Landscape light fixtures should be carefully
selected so that they are compatible with the
building, yet recognizable as a product of their
own time.
•Driveway lighting is not permitted on Aspen
Victorian properties.
•Landscape uplighting is not allowed.
Fences
Originally, wood picket fences were commonly used
to define front yards on Aspen Victorian properties.
These fences provided a subtle delineation of private
yard versus public right-of-way and were low in height,
transparent in design, and did not create walled off
private areas. The fence’s vertical slats were set apart
with spaces between, and the overall height of the
fence was approximately three feet. Many properties
traditionally had open lawns with no fencing.
Some Post-WWII properties may have original fences
that provide less transparency than those used in the
19th century, or have other unique characteristics.
Fencing on these properties will be reviewed on a
case-by-case basis.
1.15 Preserve original fences.
•Fences which are considered part of the historic
significance of a site should not be moved,
Landscape lighting that suits this AspenModern home.
A picket fence is an appropriate choice for a Victorian era
home.
cHapter 1: sIte plannIng & landscape desIgn
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46 • City of Aspen • Historic Preservation Design Guidelines
removed, or inappropriately altered.
•Replace only those portions of a historic fence
that are deteriorated beyond repair.
•Replacement elements must match the existing.
1.16 When possible, replicate a missing historic
fence based on photographic evidence.
1.17 No fence in the front yard is often the
most appropriate solution.
•Reserve fences for back yards and behind street
facing façades, as the best way to preserve the
character of a property.
1.18 When building an entirely new fence, use
materials that are appropriate to the building
type and style.
•The new fence should use materials that were
used on similar properties during the period of
significance.
•A wood fence is the appropriate solution in most
locations.
•Ornate fences, including wrought iron, may create
a false history are not appropriate for Aspen
Victorian landmarks unless there is evidence that
a decorative fence historically existed on the site.
•A modest wire fence was common locally in the
early 1900s and is appropriate for Aspen Victorian
properties. This fence type has many desirable
characteristics including transparency, a low
height, and a simple design. When this material is
used, posts should be simply detailed and not
oversized.
1.19 A new fence should have a transparent
quality, allowing views into the yard from the
street.
•A fence that defines a front yard must be low in
height and transparent in nature.
•For a picket fence, spacing between the pickets
must be a minimum of 1/2 the width of the picket.
•For Post-WWII properties where a more solid type
of fence may be historically appropriate, proposals
will be reviewed on a case-by-case basis.
•Fence columns or piers should be proportional to
the fence segment.
1.20 Any fence taller than 42” should be
designed so that it avoids blocking public views
of important features of a designated building.
This is one of the last remaining original Victorian fences in
Aspen.
A historic wire fence ;located on Cooper Ave.
A privacy fence that reflects a traditional picket fence style.
cHapter 1: sIte plannIng & landscape desIgn
A historic photograph showing both a simple wire fence and a
taller and more opaque privacy fence.
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City of Aspen • Historic Preservation Design Guidelines • 47
removed, or inappropriately altered.
•Replace only those portions of a historic fence
that are deteriorated beyond repair.
•Replacement elements must match the existing.
1.16 When possible, replicate a missing historic
fence based on photographic evidence.
1.17 No fence in the front yard is often the
most appropriate solution.
•Reserve fences for back yards and behind street
facing façades, as the best way to preserve the
character of a property.
1.18 When building an entirely new fence, use
materials that are appropriate to the building
type and style.
•The new fence should use materials that were
used on similar properties during the period of
significance.
•A wood fence is the appropriate solution in most
locations.
•Ornate fences, including wrought iron, may create
a false history are not appropriate for Aspen
Victorian landmarks unless there is evidence that
a decorative fence historically existed on the site.
•A modest wire fence was common locally in the
early 1900s and is appropriate for Aspen Victorian
properties. This fence type has many desirable
characteristics including transparency, a low
height, and a simple design. When this material is
used, posts should be simply detailed and not
oversized.
1.19 A new fence should have a transparent
quality, allowing views into the yard from the
street.
•A fence that defines a front yard must be low in
height and transparent in nature.
•For a picket fence, spacing between the pickets
must be a minimum of 1/2 the width of the picket.
•For Post-WWII properties where a more solid type
of fence may be historically appropriate, proposals
will be reviewed on a case-by-case basis.
•Fence columns or piers should be proportional to
the fence segment.
1.20Any fence taller than 42” should be
designed so that it avoids blocking public views
of important features of a designated building.
This is one of the last remaining original Victorian fences in
Aspen.
A historic wire fence ;located on Cooper Ave.
A privacy fence that reflects a traditional picket fence style.
•A privacy fence should incorporate transparent
elements to minimize the possible visual impacts.
Consider staggering the fence boards on either
side of the fence rail. This will give the appearance
of a solid plank fence when seen head on. Also
consider using lattice, or other transparent
detailing on the upper portions of the fence.
•A privacy fence should allow the building corners
and any important architectural features that are
visible from the street to continue to be viewed.
•All hedgerows (trees, shrub bushes, etc.) are
prohibited in Zones A and B.
Retaining Walls
Historically stone retaining walls were sometimes
used on steep slopes. Some of these walls survive and
are important character-defining features. Whenever
feasible they should be preserved. The addition of
retaining walls on flat sites or in locations where they
were not seen historically should be avoided.
1.21 Preserve original retaining walls
•Replace only those portions that are deteriorated
beyond repair. Any replacement materials should
match the original in color, texture, size and finish.
•Painting or covering a historic masonry retaining
wall or covering is not allowed.
•Increasing the height of a retaining wall is
inappropriate.
1.22 When a new retaining wall is necessary,
its height and visibility should be minimized.
•All wall materials, including veneer and mortar,
will be reviewed on a case by case basis and
should be compatible with the palette used on the
historic structure.
1.23 Re-grading the site in a manner that
changes historic grade is generally not allowed
and will be reviewed on a case by case basis.
A restored historic retaining wall located at 320 W. Main Street.
cHapter 1: sIte plannIng & landscape desIgn
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48 • City of Aspen • Historic Preservation Design Guidelines
cHapter 1: sIte plannIng & landscape desIgn
Cultural and Designed Landscapes
In addition to architectural landmarks, Aspen has
historical landscapes. Historic landscapes are just
as important to preservation goals as buildings. All
alterations to cultural and designed landscapes
are considered on a case-by-case basis. Some
architectural landmarks include designed landscapes
and hardscapes that blend the building into the
surrounding environment. These features are integral
to the preservation of the historic site.
1.24 Preserve historically significant
landscapes with few or no alterations.
• An analysis of the historic landscape and an
assessment of the current condition of the
landscape should be done before the beginning of
any project.
• The key features of the historic landscape and its
overall design intent must be preserved.
1.25 New development on these sites should
respect the historic design of the landscape
and its built features.
• Do not add features that damage the integrity of
the historic landscape.
• Maintain the existing pattern of setbacks and
siting of structures.
• Maintain the historic relationship of the built
landscape to natural features on the site.
• All additions to these landscapes must be clearly
identifiable as recent work.
• New artwork must be subordinate to the designed
landscape in terms of placement, height, material,
and overall appearance. Place new art away from
significant landscape features.
• Avoid installing utility trenches in cultural
landscapes if possible.
1.26 Preserve the historic circulation system.
• Minimize the impact of new vehicular circulation.
• Minimize the visual impact of new parking.
• Maintain the separation of pedestrian and vehicle
which occurred historically.
Red Butte Cemetery, one of the three historic cemeteries in
Aspen.
Herbert Bayer’s 1955 Marble Garden at the Aspen Meadows.
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City of Aspen • Historic Preservation Design Guidelines • 49
cHapter 1: sIte plannIng & landscape desIgn
1.27 Preserve and maintain significant
landscaping on site.
•Protect established vegetation during any
construction.
•If any tree or shrub needs to be removed replace it
with the same or similar species.
•New planting should be of a species used
historically or a similar species.
•Maintain and preserve any gardens and/or
ornamental planting on the site.
•Maintain and preserve any historic landscape
elements.
In 1976, several downtown streets were redesigned as
pedestrians malls.
112
113
D esign g uidelines :r e HA bilitAtion
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52 • City of Aspen • Historic Preservation Design Guidelines
cHapter 2: BuIldIng MaterIals
This chapter addresses the treatment of primary
historic building materials—those that compose the
dominant exterior surfaces of historic buildings. The
treatment of materials used for architectural trim is
addressed in a separate chapter.
In Aspen, wood siding and masonry have been the
typical primary building materials for both Aspen
Victorian and AspenModern landmarks. For Aspen
Victorian properties, horizontal clapboard is the most
common material for residences. Most downtown
buildings are brick or stone. AspenModern often
used stucco, concrete block and brick. In each case,
the distinct characteristics of the primary building
material, including the scale of the material unit, its
texture and finish, are key features that contribute to
the historic character of a building.
The best way to preserve historic building materials is
through well-planned maintenance. It is important to
inspect a historic building regularly.
Horizontal building surfaces such as chimneys, caps,
sills, railings, and parapet copings are likely to show
the most wear because they are more exposed and
may retain water for longer periods of time.
When deterioration occurs, repairing the material
rather than replacing it is preferred. It is important that
the extent of replacement materials be minimized,
because the original materials contribute to the
authenticity of the property as a historic resource. Even
when the replacement material exactly matches that
of the original, the integrity of a historic building is to
some degree compromised when extensive amounts
are removed. This is because the original material
exhibits a record of the labor and craftsmanship of
an earlier time and this is lost when materials are
replaced.
It is also important to recognize that all materials
weather over time and that an aged finish, or patina
does not represent an inferior material, but simply
reflects the longevity of the building. Preserving
original materials that show signs of wear is therefore
preferred to replacement.
AspenModern properties which exhibit deterioration
may require more substantial material replacement
in order to preserve the original design intent. For
example, CMU block that has been damaged over
time may need to be entirely replaced in order to
preserve the monochrome coloring or crisp edges
indicative of the style. Approval of replacement
materials on AspenModern properties is handled on
a case by case basis.
Treatment of Materials
2.1 Preserve original building materials.
•Do not remove siding that is in good condition
or that can be repaired in place.
•Masonry features that define the overall historic
character, such as walls, cornices, pediments,
steps and foundations, should be preserved.
•Avoid rebuilding a major portion of an exterior
wall that could be repaired in place. Reconstruction
may result in a building which no longer retains its
historic integrity.
•Original AspenModern materials may be
replaced in kind if it has been determined that
the weathering detracts from the original design
intent or philosophy.
c HApter 2: b uilding MAteriAls
Policy: Historic building materials should be
preserved in place whenever feasible. When the
material is damaged, then limited replacement
that matches the original in appearance
should be considered. Primary historic building
materials should never be covered or subjected
to harsh cleaning treatments.
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City of Aspen • Historic Preservation Design Guidelines • 53
cHapter 2: BuIldIng MaterIals
2.2 The finish of materials should be as it
would have existed historically.
•Masonry naturally has a water-protective layer to
protect it from the elements. Brick or stone that
was not historically painted shall not be painted.
•If masonry that was not painted historically was
given a coat of paint at some more recent time,
consider removing it, using appropriate methods.
•Wood should be painted, stained or natural, as
appropriate to the style and history of the building.
Replacement of Materials
2.3 Match the original material in composition,
scale and finish when replacing materials on
primary surfaces.
•If the original material is wood clapboard for
example, then the replacement material must be
wood as well. It should match the original in size,
and the amount of exposed lap and finish.
•Replace only the amount required. If a few boards
are damaged beyond repair, then only those should
be replaced, not the entire wall. For AspenModern
buildings, sometimes the replacement of a larger
area is required to preserve the integrity of the
design intent.
2.4 Do not use synthetic materials as
replacements for original building materials.
•Original building materials such as wood siding
and brick should not be replaced with synthetic
materials.
Covering Materials
2.5 Covering original building materials with
new materials is inappropriate.
•Regardless of their character, new materials
obscure the original, historically significant
material.
•Any material that covers historic materials may
also trap moisture between the two layers. This
will cause accelerated deterioration to the historic
material which may go unnoticed.
2.6 Remove layers that cover the original
material.
•Once the non-historic siding is removed, repair
the original, underlying material.
Monitor the condition of horizontal surfaces that collect snow
and water.
Repair of historic siding in preparation for new paint.
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54 • City of Aspen • Historic Preservation Design Guidelines
Before: Building prior to alteration.After: A cornice has been installed over the original brick.
cHapter 2: BuIldIng MaterIals
Before: A sign was installed overtop of the original decorative
molding.
After: The molding after restoration.
After: The same house after non-historic siding materials were
removed to expose original clapboard.
Before: The original siding on this house was covered with
asbestos shingles.
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City of Aspen • Historic Preservation Design Guidelines • 55
cHapter 3: wIndows
Background
Windows are some of the most important character-
defining features of historic structures. They give
scale to buildings and provide visual interest to the
composition of individual façades. In fact, distinct
window designs help define many historic building
styles. For example, AspenModern properties in
the Wrightian/Organic style typically have mitered
windows that blur the line between the outside and
the inside. The treatment of a historic window and
the addition of a new opening to a historic structure
requires careful consideration.
Key Features of Windows
The size, shape, location, and proportions of historic
windows are among their essential features. Many
Aspen Victorian windows were “double hung” with two
sliding vertical sashes. These windows were usually
sparsely placed around the structure. In contrast,
a key defining feature of the Modern Chalet is large
areas of glazing spanning from floor to roofline. The
design of window casings, the depth and profile of
window sash elements and the materials of which they were constructed are also important features.
Window Types
Window types typically found on Aspen landmarks
include:
•Casement - Hinged windows that swing open
typically to the outside.
•Double Hung - Two sash elements, one above the
other; both upper and lower sashes slide within
tracks on the window jambs.
•Single Hung - Two sash elements, one above the
other; only the lower sash moves.
•Fixed - The sash does not move.
•Mitered - Also called butt glazed windows, two
windows joined together create a 90 degree
corner.
Casement windows.
Double hung windows.
Policy: The character-defining features
of historic windows and their distinctive
arrangement on a wall should be preserved.
This is especially important on primary façades.
New windows should be in character with the
historic building.
c HApter 3: windows
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56 • City of Aspen • Historic Preservation Design Guidelines
cHapter 3: wIndows
Deterioration of Historic Windows
Properly maintained, original windows will provide
excellent service for centuries. Most problems that
occur result from a lack of proper maintenance.
Water damage and the ultra-violet degradation caused
by sunlight are major concerns, specifically for wood
windows. If surfaces fail to drain properly, water may
be introduced which quickly begins to cause material
damage. In most cases, windows are protected if a
good coat of paint or stain is maintained.
Repair or Replacement of Historic Windows
Whenever possible, repair a historic window, rather
than replace it. In most cases it is in fact more
economical to repair the existing frame and glass
rather than to replace them. Even when replaced with
an exact duplicate window, a portion of the historic
building fabric is lost when new windows are installed,
and therefore such treatment should be avoided.
Inspect historic windows to determine their condition.
Distinguish superficial signs of deterioration from
actual failure of window components. Peeling paint,
dried wood, or a rotted sill, for example, are serious
problems, but often do not indicate that a window is
beyond repair. Patching and splicing in new material
for only those portions that are decayed is preferred.
Complete window replacement will only be approved
when unavoidable, on a case-by-case basis.
While replacing an entire window assembly is
discouraged, it may be necessary in some cases.
When a window is to be replaced, the new one
should match the appearance of the original to the
greatest extent possible, including the material, size
and proportion of window elements, glass and sash
components, the original profile, and the original
depth of the window opening.
Energy Conservation
In some cases, owners may be concerned that an older
window is inefficient in terms of energy conservation.
In winter, for example, heat loss associated with an
older window may make a room uncomfortable
and increase heating costs. In fact, most heat loss
is associated with air leakage though gaps that are
the result of a lack of maintenance, rather than loss
of energy through the single pane of glass found in
historic windows. The glazing compound may be
cracked or missing, allowing air to move around the
glass. Sash members also may have shifted, leaving
a gap for heat loss. Adding a storm window, which
Fixed windows.
Mitered windows.
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City of Aspen • Historic Preservation Design Guidelines • 57
cHapter 3: wIndows
Before: Window and door openings filled in with non-historic
materials.
was typical practice in the 19th century, or weather
stripping successfully addresses air leakage while
preserving the historic window.
Treatment of Windows
3.1 Preserve the functional and decorative
features of a historic window.
•Features important to the character of a window
include its frame, sash, muntins/mullions,
sills, heads, jambs, moldings, operations, and
groupings of windows.
•Repair frames and sashes rather than replacing
them.
•Preserve the original glass. If original Victorian
era glass is broken, consider using restoration
glass for the repair.
3.2 Preserve the position, number, and
arrangement of historic windows in a building
wall.
•Enclosing a historic window is inappropriate.
•Do not change the size of an original window
opening.
Replacement of Windows that are
Beyond Repair, or Have Been Removed
3.3 Match a replacement window to the original
in its design.
•If the original is double-hung, then the replacement
window must also be double-hung. If the sash
have divided lights, match that characteristic as
well.
3.4 When replacing an original window, use
materials that are the same as the original.
3.5 Preserve the size and proportion of a
historic window opening.
•Changing the window opening is not permitted.
•Consider restoring an original window opening
that was enclosed in the past.
3.6 Match, as closely as possible, the profile
of the sash and its components to that of the
original window.
•A historic window often has a complex profile.
Within the window’s casing, the sash steps back
to the plane of the glazing (glass) in several
After: Restored storefront.
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58 • City of Aspen • Historic Preservation Design Guidelines
cHapter 3: wIndows
After: Restored windows.
Before: Look for evidence of original openings and restore.
increments. These increments, which individually
only measure in eighths or quarters of inches, are
important details. They distinguish the actual
window from the surrounding plane of the wall.
•The historic profile on AspenModern properties is
typically minimal.
Adding Windows
3.7 Adding new openings on a historic structure
is generally not allowed.
•Greater flexibility in installing new windows may
be considered on rear or secondary walls.
•New windows should be similar in scale to the
historic openings on the building, but should in
some way be distinguishable as new, through the
use of somewhat different detailing, etc.
•Preserve the historic ratio of window openings
to solid wall on a façade.
•Significantly increasing the amount of glass on
a character defining façade will negatively affect
the integrity of a structure.
Energy Conservation
3.8 Use a storm window to enhance energy
conservation rather than replace a historic
window.
•Install a storm window on the interior, when
feasible. This will allow the character of the
original window to be seen from the public way.
•If a storm window is to be installed on the exterior,
match the sash design and material of the original
window. It should fit tightly within the window
opening without the need for sub-frames or
panning around the perimeter. A storm window
should not include muntins unless necessary for
structure. Any muntin should be placed to match
horizontal or vertical divisions of the historic
window.
Exterior mounted wood storm windows.
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City of Aspen • Historic Preservation Design Guidelines • 59
cHapter 4: doors
Background
Doors are important character-defining features
of historic structures, which give scale to buildings
and provide visual interest to the composition of
individual façades. Many historic doors are noted for
their materials, placement and finishes.
Door Features
Important features include the materials and details
of the door itself, its frame, sill, head, jamb and any
flanking windows or transoms.
Door Types
Door types found on historic structures in Aspen
include:
•Doorway with transom - Typically a wooden
door topped with a rectangular transom with
glass.
•Half-lite door - This type of door has a wide sash
of glass in the upper portion of the door. Many
early Aspen houses have half-lite doors.
•Full-lite door - This type of door is predominantly
glass.
•Paneled door - Wooden door with raised panels.
•Slab door - A door without panels or glass.
Full-lite door.
Policy: The character-defining features of a
historic door and its distinct materials and
placement should be preserved. A new door
should be in character with the historic building.
c HApter 4: doors
Doorway with transom.
Half-lite door with double arched windows.
Slab door.
122
60 • City of Aspen • Historic Preservation Design Guidelines
cHapter 4: doors
Deterioration
A typical Aspen Victorian door is sheltered by a
porch, which extends the life of the door. However,
deterioration can still occur due to water damage,
weathering, and constant use. AspenModern
properties typically have minimal roof overhangs or
porches. As a result of deterioration, some historic
doors do not properly fit their openings and allow
moisture and air into the building.
Repair of Historic Doors
A problem door sometimes just needs to be re-hung
in order to properly work. If is often easier and more
economical to repair an existing door rather than
to replace it. This is preferred because the original
materials contribute to the historic character of the
building. Even when replaced with an exact duplicate,
a portion of the historic building fabric is lost and such
treatment should be avoided.
When rehabilitating a historic door it is important to
maintain original doors, jambs, transoms, window
panes and hardware. Surfaces may require cleaning
and patching and some components may be
deteriorated beyond repair. Patching and splicing in
new material for only those portions that are decayed
should be considered in such a case, rather than
replacing the entire door.
Replacement Doors
Replacing an entire door assembly is discouraged.
When a door must be replaced, the new one should
match the original. A frequent concern is the material
of the replacement door. Using the same material as
the original is required. If the historic door was wood,
then use a wood replacement. It is important to
preserve the original jamb when feasible.
Door Function
The historic front door on a primary façade must be
the main entrance into the building. Aspen Victorians
with two front doors are permitted to fix one of
the doors in place so that it does not operate. The
procedure to fix the door must be reversible.
Energy Conservation
Owners may be concerned about the energy efficiency
of old doors that seem to leak cold air during the
winter. Most heat loss is associated with air leakage
through the space below the door.
The most cost-effective energy conservation measure
for a typical historic door is to install weather stripping
Door at 827 dean street.
123
Caption
Caption
City of Aspen • Historic Preservation Design Guidelines • 61
cHapter 4: doors
along the door, to fit the door to the jamb and threshold
and to caulk any window panes. These measures
will dramatically reduce heat loss while preserving
historic features. If additional energy savings are a
concern, consider installing a storm door. This may be
applied to the exterior of the door. If a storm door is to
be installed, it should match the design and materials
of the original door.
Treatment of Existing Doors
These guidelines for the treatment of doors apply to
all existing and proposed exterior doors, and screen
doors.
4.1 Preserve historically significant doors.
•Maintain features important to the character
of a historic doorway. These include the door,
door frame, screen door, threshold, glass panes,
paneling, hardware, detailing, transoms and
flanking sidelights.
•Do not change the position and function of original
front doors and primary entrances.
•If a secondary entrance must be sealed shut, any
work that is done must be reversible so that the
door can be used at a later time, if necessary. Also,
keep the door in place, in its historic position.
•Previously enclosed original doors should be
reopened when possible.
4.2 Maintain the original size of a door and its
opening.
•Altering its size and shape is inappropriate. It
should not be widened or raised in height.
4.3 When a historic door or screen door is
damaged, repair it and maintain its general
historic appearance.
Replacement Doors
4.4 When replacing a door or screen door, use
a design that has an appearance similar to the
original door or a door associated with the style
of the building.
•A replica of the original, if evidence exists, is the
preferred replacement.
•A historic door or screen door from a similar
building also may be considered.
•Simple paneled doors were typical for Aspen
Victorian properties.
Many Victorian era homes in Aspen had two front doors; one
for receiving guests and one for family use.
A new screen door.
An original screen door must be preserved.
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62 • City of Aspen • Historic Preservation Design Guidelines
cHapter 4: doors
• Very ornate doors, including stained or leaded
glass, are discouraged, unless photographic
evidence can support their use.
Adding Doors
4.5 Adding new doors on a historic building is
generally not allowed.
• Place new doors in any proposed addition rather
than altering the historic resource.
• Greater flexibility in installing a door in a new
location may be considered on rear or secondary
walls.
• A new door in a new location should be similar in
scale and style to historic openings on the building
and should be a product of its own time.
• Preserve the historic ratio of openings to solid wall
on a façade. Significantly increasing the openings
on a character defining façade negatively affects
the integrity of a structure.
Energy Conservation
4.6 If energy conservation and heat loss are
concerns, use a storm door instead of replacing
a historic entry door.
• Match the material, frame design, character, and
color of the primary door.
• Simple features that do not detract from the
historic entry door are appropriate for a new
storm door.
• New storm or screen doors should be in character
with the primary door.
Door Hardware
4.7 Preserve historic hardware.
• When new hardware is needed, it must be in scale
with the door and appropriate to the style of the
building.
• On Aspen Victorian properties, conceal any
modern elements such as entry key pads.
A decorative door knob.
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City of Aspen • Historic Preservation Design Guidelines • 63
cHapter 5: porcHes & BalconIes
Background
In the 19th century, front, side and rear porches
were popular features in residential design. A porch
protects an entrance from snow and provides shade
in the summer. It also provides a sense of scale and
aesthetic quality to the façade of a building. A porch
often connects a house to its context by orienting the
entrance to the street. Because of their importance as
character-defining features, porches should receive
sensitive treatment during exterior rehabilitation and
restoration work.
Some AspenModern styles employed recessed entries
and roof overhangs as porches. Open balconies are
common on Chalet and Modern Chalet buildings.
Key Features
Porches and balconies vary as much as architectural
styles. They differ in height, scale, location, materials
and articulation. A porch or balcony may be cut in,
project or wrap around a corner and it may have
elaborate details and finishes. Although they vary in
character, most Aspen Victorian porches have these
elements in common:
•Balustrades or railings
•Posts/columns
•Architectural details
•Hipped/shed/flat roofs
These elements often correspond to the architectural
style of the house and therefore, the building’s design
character should be considered before any major
rehabilitation or restoration work is done.
AspenModern properties sometimes feature
traditional porches, but may have balconies which
run the full width or length of a structure and sit 1/2
story of a full story above the ground. The balustrade
may be decorative or simple squared rails.
Policy: An original porch or balcony should
be preserved. In cases where the feature has
been altered, it should be restored to its original
appearance.
c HApter 5: p orcHes & bAlconies
An entry porch on a Pan Abode building.
A Victorian porch.
A balcony on a Chalet.
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64 • City of Aspen • Historic Preservation Design Guidelines
cHapter 5: porcHes & BalconIes
Deterioration
Because of constant exposure to sun and rain and the
fact that a porch or balcony is open to the elements,
it decays faster than other portions of a building.
Furthermore, if water is not channeled away from the
foundation of a porch, its footings may be damaged.
Peeling paint is a common symptom. In some
cases a porch or balcony may experience sagging or
detachment from the main structure due to settling.
Repair of Porches
After discovering structural or cosmetic problems,
a porch or balcony should be repaired rather than
replaced. Repair is preferred to replacement because
the original materials contribute to the historic
character of the porch. Even when replaced with an
exact duplicate, a portion of the historic building fabric
is lost; therefore, such treatment should be avoided
when feasible.
Reconstructing a porch or balcony that is
beyond repair or has been removed
When reconstruction is necessary, research the
history of the building to determine the original design
of the feature. Look for physical evidence including
“ghost lines” on walls that indicate the outline of
the features as it once existed. Reference similar
buildings for guidance if needed.
Treatment
5.1 Preserve an original porch or balcony.
•Replace missing posts and railings when
necessary. Match the original proportions,
material and spacing of balusters.
•Expanding the size of a historic porch or balcony
is inappropriate.
5.2 Avoid removing or covering historic
materials and details.
•Removing an original balustrade, for example, is
inappropriate.
5.3 Enclosing a porch or balcony is not
appropriate.
•Reopening an enclosed porch or balcony is
appropriate.
Before: A historic porch where the original posts and details
were replaced with an inaccurate design.
Handrails are susceptible to deterioration.
After: A restored porch based on historic documentation.
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City of Aspen • Historic Preservation Design Guidelines • 65
cHapter 5: porcHes & BalconIes cHapter 5: porcHes & BalconIes
Reconstruction
5.4 If reconstruction is necessary, match the
original in form, character and detail.
• Match original materials.
• When reconstructing an original porch or balcony
without historic photographs, use dimensions and
characteristics found on comparable buildings.
Keep style and form simple with minimal, if any,
decorative elements.
Steps, Handrails, and Guardrails
5.5 If new steps are to be added, construct
them out of the same primary materials used
on the original, and design them to be in scale
with the porch or balcony
• Steps should be located in the original location.
• Step width should relate to the scale of entry
doors, spacing between posts, depth of deck, etc.
• Brick, red sandstone, grey concrete, or wood are
appropriate materials for steps.
5.6 Avoid adding handrails or guardrails where
they did not exist historically, particularly
where visible from the street.
• If handrails or guardrails are needed according
to building code, keep their design simple in
character and different from the historic detailing
on the porch or balcony.
Before: An enclosed porch significantly changes the character
of the historic structure.
After: The porch is restored, based on historic documentation.
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66 • City of Aspen • Historic Preservation Design Guidelines
cHapter 6: arcHItectural detaIls
Background
Architectural details play several roles in defining the
character of a historic structure. They add visual
interest, distinguish certain building styles and types,
and often showcase superior craftsmanship. While
architectural details on many styles are ornamental in
nature, some are very simple. In both cases, the
character of the details contributes to the significance
of historic properties. Features such as window
hoods, brackets and posts exhibit materials and
finishes often associated with particular styles.
Treatment & Repair
Preserving original architectural details is critical to
the integrity of the building. Where replacement is
required, one should remove only those portions that
are deteriorated beyond repair. Even if an architectural
detail is replaced with an exact copy of the original,
the integrity of the building as a historic resource is
diminished. Therefore, preservation of the original
material is preferred.
Replacement
Using a material to match the historic material is
always the best approach. In unique circumstances,
a substitute material may be considered when it
appears similar in composition, design, color, and
texture to the original. Substitute materials may be
considered when the original is not available, where
the original is known to be susceptible to rapid decay,
or where maintenance access may be difficult.
Treatment of Architectural Features
6.1 Preserve significant architectural features.
• Repair only those features that are deteriorated.
• Patch, piece-in, splice, or consolidate to repair the
existing materials, using recognized preservation
methods whenever possible.
• On AspenModern properties, repair is preferred,
however, it may be more important to preserve the
Policy: Architectural details help establish a
historic building’s distinct visual character and
should be preserved. If architectural details are
damaged beyond repair, replacements should
match the original detailing.
c HApter 6: Arc HitecturA l detAils
An ornate Queen Anne home.
Simple miner’s cottage with ornate details.
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City of Aspen • Historic Preservation Design Guidelines • 67
cHapter 6: arcHItectural detaIls
integrity of the original design intent, such as crisp
edges, rather than to retain heavily deteriorated
material.
6.2 When disassembly of a historic element is
necessary for its restoration, use methods that
minimize damage to the original material.
• Document its location so it may be repositioned
accurately. Always devise methods of replacing
the disassembled material in its original
configuration.
6.3 Remove only the portion of the detail that
is deteriorated and must be replaced.
• Match the original in composition, scale, and
finish when replacing materials or features.
• If the original detail was made of wood, for
example, then the replacement material should
be wood, when feasible. It should match the
original in size and finish.
6.4 Repair or replacement of missing or
deteriorated features are required to be based
on original designs.
• The design should be substantiated by physical
or pictorial evidence to avoid creating a
misrepresentation of the building’s heritage.
• When reconstruction of an element is impossible
because there is no historical evidence, develop
a compatible new design that is a simplified
interpretation of the original, and maintains
similar scale, proportion and material.
6.5 Do not guess at “historic” designs for
replacement parts.
• Where scars on the exterior suggest that
architectural features existed, but there is no
other physical or photographic evidence, then
new features may be designed that are similar in
character to related buildings.
• Using ornate materials on a building or adding
new conjectural detailing for which there is no
documentation is inappropriate.
Broken balusters within this railing were carefully replicated.
The Health Club at the Aspen Meadows features a simple, but
carefully detailed fascia.
A portion of the metal crown on the Elks Building was missing
and needed to be replicated.
The restored dome on the Elks Building.
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68 • City of Aspen • Historic Preservation Design Guidelines
cHapter 7: rooFs
Background
The character of the roof is a major feature for most
historic structures. In each case, the roof pitch,
materials, size and orientation are all distinct features
that contribute to its character. Aspen Victorian
properties have a range of gabled, hip, shed, and flat
roof forms depending on building type. AspenModern
properties typically have a range of gable, parabolic,
butterfly or flat roof forms depending on the
architectural style. Although the function of a roof is
to protect a structure from the elements, it contributes
to overall architectural character of the building.
Characteristics Most Associated with Aspen
Architectural Styles
• Deep Overhangs - Chalet, Modern Chalet, Rustic,
Wrightian
• Flat roof, minimal eaves - Modern
• Gables, shed - Victorian
Deterioration
The roof is the structure’s main defense against the
elements. Over time all components of the roofing
system are vulnerable to leaking and damage. When
the roof begins to experience failure it can affect other
parts of the structure by no longer acting as a barrier
from water, wind, and exposure. Common sources of
roof leaks include:
• Cracks in chimney masonry
• Loose flashing around chimneys and ridges
• Loose or missing roof shingles
• Cracks in roof membranes caused by settling
rafters
• Water backup from plugged gutters
• Ice dams
Policy: The character of a historical roof,
including its form and materials, should be
preserved.
c HApter 7: roofs
Deep overhangs on a Chalet.
An A-Frame roof form on a Fritz Benedict designed home.
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City of Aspen • Historic Preservation Design Guidelines • 69
cHapter 7: rooFs
Repairing a Historic Roof
When repairing a historic roof it is important to
preserve its historic character. It is not appropriate
to alter the pitch of a historic roof, or to change the
orientation of the roof to the street. Eave overhangs
are extremely important to the style of the house and
should be preserved.
Gutters, Downspouts, Snowstops, and Snow
Fences
Gutters and downspouts are used to divert water
away from a structure. Without this drainage system,
water may splash off the roof onto exterior walls and
run along the foundation of the building. Snowstops
and snow fences are used to protect inhabitants and
the building from the sudden snow avalanches that
rip off architectural details and can cause serious
injury. Gutters can be seen in some 19th century
photos of historic buildings and are more common on
AspenModern structures. Overall, the visual impact
of these functional elements should be minimized.
Dormers
Historically, a dormer was sometimes added to create
more head room and light in an attic. It typically had
a vertical emphasis and was usually placed as a
single element or in a pair on a roof. A dormer did not
dominate a roof form. A new dormer should always
read as a subordinate element to the primary roof
plane. A new dormer should never be so large that
the original roof line is obscured. It should also be set
back from the roof edge and located below the roof
ridge. In addition, the style of the new dormer should
be in keeping with that of the building. Dormers are
generally foreign to some architectural styles, such
as Modernism.
Roof Materials
Exterior roof materials like shingles are usually not
original on Aspen Victorian properties due to age
and replacement over time. Periodic replacement
of roofing is accepted. However, roof sheathing
and structure is typically original on most of these
buildings should be preserved. When repairing or
altering a historic roof, do not remove significant
materials that are in good condition. Always repair
materials when feasible. For example, sister beams
when roof rafters need more structural integrity
rather than removing and replacing the element.
Where replacement is necessary, use a material that
is similar to the original in style and texture. Some
AspenModern styles exposed roof rafters under deep
overhangs as part of the architectural style. These
character defining features must be preserved.
Preserve original roof cresting, as found on the Sardy House.
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cHapter 7: rooFs
Additions to Roofs
Many Aspen residences have original chimneys.
Wood burning appliances are no longer allowed in the
City of Aspen, which means that historic chimneys
are being retrofitted to accommodate other vents.
New venting of any type added to a roof should be low
profile, carefully located, and painted a matte black or
dark color to not detract from the historic chimney.
Treatment of Roofs
7.1 Preserve the original form of a roof.
•Do not alter the angle of a historic roof. Preserve
the orientation and slope of the roof as seen from
the street.
•Retain and repair original and decorative roof
detailing.
•Where the original roof form has been altered,
consider restoration.
7.2 Preserve the original eave depth.
•Overhangs contribute to the scale and detailing of
a historic resource.
•AspenModern properties typically have very deep
or extremely minimal overhangs that are key
character defining features of the architectural
style.
7.3 Minimize the visual impacts of skylights
and other rooftop devices.
•Skylights and solar panels are generally not
allowed on a historic structure. These elements
may be appropriate on an addition.
7.4 New vents should be minimized, carefully,
placed and painted a dark color.
•Direct vents for fireplaces are generally not
permitted to be added on historic structures.
•Locate vents on non-street facing facades.
•Use historic chimneys as chases for new flues
when possible.
7.5 Preserve original chimneys, even if they
are made non-functional.
•Reconstruct a missing chimney when
documentation exists.
7.6 A new dormer should remain subordinate
to the historic roof in scale and character.
•A new dormer is not appropriate on a primary,
These new chimney vents are consistent with the building
type, located behind the ridgeline, and a dark color.
This non-historic chimney is overscaled for the miner’s
cottage.
Before: Skylights are inappropriate on a miner’s cottage.
After: The historic resource after the skylights were removed.
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City of Aspen • Historic Preservation Design Guidelines • 71
cHapter 7: rooFs
Materials
7.7 Preserve original roof materials.
7.8 New or replacement roof materials should
maintain or restore the character of the historic
roof.
7.9 Avoid using conjectural features on a roof.
Before: A historic resource before dormers were added.
After: New dormers that are too large can change the massing
of the original building.
Preserve original roof material when possible.
•
•
•
•
character defining façade.
A new dormer should fit within the existing wall
plane. It should be lower than the ridgeline and
set in from the eave. It should also be in
proportion with the building.
The mass and scale of a dormer addition must be
subordinate to the scale of the historic building.
While dormers improve the livability of upper floor
spaces where low plate heights exist, they also
complicate the roof and may not be appropriate
on very simple structures.
Dormers are generally not permitted on
AspenModern properties since they are not
characteristic of these building styles.
•
•
Avoid removing historic roofing material.
Using recognized preservation methods, repair
deteriorated historic material when possible.
When replacement is necessary, replace the
roofing in kind, and/or use a material that is
similar to the original in both style and physical
qualities.
•
•
•
•
•
If a substitute is used, the roof material should be
of a design, scale, color, texture, and composition
akin to the original, or a simplified, neutral,
modest, and deferential alternative that is
visually compatible with the building's historic
features.
Flashing should be in scale with the roof
material.
Flashing should be tin, lead coated copper,
galvanized or painted metal and have a matte,
non-reflective finish.
Design flashing, such as drip edges, so that
architectural details are not obscured.
A metal roof material should have a matte, non-
reflective finish and match the original seaming.
•
•
•
Adding ornament or detail where there is no evidence that it existed, creates a false impression of
the building's original appearance, and is inappropriate.
Roofing materials should reflect the architectural style of the affected building or be substantiated by
documentary or physical evidence
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cHapter 7: rooFs
7.10 Design gutters so that their visibility
on the structure is minimized to the extent
possible.
•Downspouts should be placed in locations that
are not visible from the street if possible, or
in locations that do not obscure architectural
detailing on the building.
•The material used for the gutters should be in
character with the style of the building.
These simple gutters are in character with a miner’s cottage.
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City of Aspen • Historic Preservation Design Guidelines • 73
cHapter 8: secondary structures
This chapter addresses the treatment of secondary
structures. These guidelines apply in addition to
the guidelines for treatment of doors, windows,
roofs, materials, additions and architectural details
presented in the preceding chapters.
Secondary structures include detached garages,
carriage houses, and sheds. Traditionally, these
structures were important elements of 19th
century residential sites in particular. Secondary
structures help interpret how an entire site was used
historically. Most secondary structures are simple in
form, materials, and detailing, reflecting their more
utilitarian functions. Because secondary structures
are subordinate to a primary building, greater
flexibility in their treatment may be considered, but
their preservation is a priority.
Secondary Structures
8.1 If an existing secondary structure is
historically significant, then it must be
preserved.
• When treating a historic secondary building,
respect its character-defining features. These
include its materials, roof form, windows, doors,
and architectural details.
• If a secondary structure is not historically
significant, then its preservation is optional.
The determination of significance is based
on documentation of the construction date of
the outbuilding and/or physical inspection. A
secondary structure that is related to the period
of significance of the primary structure will likely
require preservation.
8.2 Preserve a historic secondary building as a
detached structure.
• Any proposal to attach a secondary structure is
reviewed on a case-by-case basis.
• The position and orientation of the structure
• should be maintained except when HPC finds that
an alternative is the best preservation option.
• Some AspenModern properties incorporated
garages and carports into the architecture. This
pattern should be maintained.
This carriage house illustrates how Victorian secondary
buildings were typically placed along alleys.
Policy: When a secondary structure is
determined to be historically significant, it must
be preserved. This may include keeping the
structure in its present condition or, rehabilitating
it or adapting it to a new use so that the building
continues to serve a useful function.
Note: Outbuildings often encroach into the
alleys or at least into setbacks. The owner
should be aware of variances or encroachment
licenses that may be required to renovate these
buildings. Typically an outbuilding that is over a
property line must be moved entirely onto one
lot during a major redevelopment.
c HApter 8: s econdAry structures
136
Policy: An original porch should be preserved.
In cases where the porch has been altered, it
should be restored to its original appearance.
74 • City of Aspen • Historic Preservation Design Guidelines
cHapter 8: secondary structures
8.3 Do not add detailing or features to a
secondary structure that are conjectural and
not in keeping with its original character as a
utilitarian structure.
•Most secondary structures are basic rectangular
solids, with simple finishes and no ornamentation.
8.4 When adding on to a secondary structure,
distinguish the addition as new construction
and minimize removal of historic fabric.
•Additions to a secondary structure must be
smaller in footprint than the original building and
lower in height. Maintaining the overall mass and
scale is particularly important.
•Do not alter the original roof form.
•An addition must be inset from the corners of the
wall to which it attaches.
8.5 Preserve the original building materials, or
match in kind when necessary.
8.6 Preserve original door and window
openings and minimize new openings.
•If an original carriage door exists, and can be made
to function for automobile use, this is preferred.
8.7 If a new garage door is added, it must be
compatible with the character of the historic
structure.
•The materials and detailing should be simple.
8.8 Adaptation of an obsolete secondary
structure to a functional use is encouraged.
•The reuse of any secondary structure should be
sensitive so that its character is not lost.
After: The same outbuilding, after restoration, contributes to
the collection of small structures along the alley.
Before: Outbuildings can fall into disuse and disrepair.
When converting an outbuilding for vehicular use, install a
simple garage door.
This former barn has been adapted for residential use, with
character defining features preserved.
137
d esign g uidelines : n ew c onstruction
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76 • City of Aspen • Historic Preservation Design Guidelines
cHapter 9: excavatIon, BuIldIng relocatIon, & FoundatIons
This chapter presents guidelines for constructing
basements, relocating historic structures and
installing new foundations. The guidelines apply to
primary and secondary structures.
The original placement of a building on its site is an
important aspect of history, contributes to integrity
and authenticity, and should be preserved.
Historic records indicate that structures have been
occasionally moved within the City reaching back into
the Victorian era, therefore, some precedent exists.
Today, however, such relocation must be considered
carefully.
Installing a foundation that meets modern standards
can be very beneficial to the long term condition of the
building. Ideally the structure will not be permanently
repositioned as part of this process.
It may be acceptable to reposition a structure
on its original site if doing so will accommodate
other compatible improvements that will assure
preservation. For example, if a house straddles two
parcels, shifting it to one side may accommodate
construction of a new, detached structure. Doing so
may better protect the scale of the original structure,
as opposed to erecting a large addition in close
proximity to the landmark.
Preserving Building Locations and
Foundations
9.1 Developing a basement by underpinning
and excavating while the historic structure
remains in place may help to preserve the
historic fabric.
•This activity will require the same level of
documentation, structural assessment, and
posting of financial assurances as a building
relocation.
9.2 Proposals to relocate a building will be
considered on a case-by-case basis
•In general, on-site relocation has less of an impact
on individual landmark structures than those in a
historic district.
•In a district, where numerous adjacent historic
structures may exist, the way that buildings were
placed on the site historically, and the open yards
visible from the street are characteristics that
should be respected in new development.
•Provide a figure ground study of the surrounding
parcels to demonstrate the effects of a building
relocation.
•In some cases, the historic significance of the
structure, the context of the site, the construction
technique, and the architectural style may make
on-site relocation too impactful to be appropriate.
It must be demonstrated that on-site relocation
is the best preservation alternative in order for
approval to be granted.
•If relocation would result in the need to reconstruct
a substantial area of the original exterior surface
of the building above grade, it is not an appropriate
preservation option.
9.3 Site a relocated structure in a position
similar to its historic orientation.
•It must face the same direction and have a
relatively similar setback. In general, a forward
movement, rather than a lateral movement is
preferred. HPC will consider setback variations
Policy: Moving a historic structure is discouraged;
however, in some instances it may be the most
appropriate option. Generally, buildings must
be relocated within the boundaries of their
original site. Permanent off-site relocation is
detrimental and will only be allowed when no
other preservation alternative is available.
c HApter 9: e xcAvAtion , b uilding r elocAtion & foundAtions
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City of Aspen • Historic Preservation Design Guidelines • 77
cHapter 9: excavatIon, BuIldIng relocatIon, & FoundatIons
where appropriate.
•A primary structure may not be moved to the rear
of the parcel to accommodate a new building in
front of it.
•Be aware of potential restrictions against locating
buildings too close to mature trees. Consult with
the City Forester early in the design process.
Do not relocate a building so that it becomes
obscured by trees.
9.4 Position a relocated structure at its historic
elevation above grade.
•Raising the finished floor of the building slightly
above its original elevation is acceptable if needed
to address drainage issues. A substantial change
in position relative to grade is inappropriate.
•Avoid making design decisions that require code
related alterations which could have been avoided.
In particular, consider how the relationship to
grade could result in non-historic guardrails, etc.
9.5 A new foundation shall appear similar in
design and materials to the historic foundation.
•On modest structures, a simple foundation is
appropriate. Constructing a stone foundation on
a miner’s cottage where there is no evidence that
one existed historically is out of character and is
not allowed.
•Exposed concrete or painted metal flashing are
generally appropriate.
•Where a stone or brick foundation existed
historically, it must be replicated, ideally using
stone salvaged from the original foundation as a
veneer. The replacement must be similar in the
cut of the stone and design of the mortar joints.
•New AspenModern foundations shall be handled
on a case by case basis to ensure preservation of
the design intent.
9.6 Minimize the visual impact of lightwells.
•The size of any lightwell that faces a street should
be minimized.
•Lightwells must be placed so that they are not
immediately adjacent to character defining
features, such as front porches.
•Lightwells must be protected with a flat grate,
rather than a railing or may not be visible from a
street.
•Lightwells that face a street must abut the
building foundation and generally may not “float”
The original sandstone was used as a veneer on this foundation
after a new basement was built.
Storing the historic resource on site during construction of the
new foundation is strongly preferred.
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cHapter 9: excavatIon, BuIldIng relocatIon, & FoundatIons
in the landscape except where they are screened,
or on an AspenModern site.
9.7 All relocations of designated structures
shall be performed by contractors who
specialize in moving historic buildings, or can
document adequate experience in successfully
relocating such buildings.
•The specific methodology to be used in
relocating the structure must be approved by the
HPC.
•During the relocation process, panels must be
mounted on the exterior of the building to protect
existing openings and historic glass. Special care
shall be taken to keep from damaging door and
window frames and sashes in the process of
covering the openings. Significant architectural
details may need to be removed and securely
stored until restoration.
•The structure is expected to be stored on its
original site during the construction process.
Proposals for temporary storage on a different
parcel will be considered on a case by case basis
and may require special conditions of approval.
•A historic resource may not be relocated outside
of the City of Aspen.
9.8 Proposals to relocate a building to a new
site are highly discouraged.
•Permanently relocating a structure from where it
was built to a new site is only allowed for special
circumstances, where it is demonstrated to be the
only preservation alternative.
Temporary off-site storage of a structure requires special
efforts to protect historic features.
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City of Aspen • Historic Preservation Design Guidelines • 79
cHapter 10: BuIldIng addItIons
Background
This chapter presents guidelines for the construction
of additions to historic structures. They apply to
primary and secondary structures. Some special
references are made to additions planned in historic
districts.
Many historic buildings in Aspen, including secondary
structures, were expanded over time as the need
for more space occurred. Typically the addition
was subordinate in scale and character to the main
building. The height of the addition was usually lower
than that of the main structure and was often located
to the side or rear, such that the original building
retained its prominence.
The addition was often constructed of materials that
were similar to those used on the original structure.
This tradition of adding onto buildings is appropriate to
continue. It is important, however, that a new addition
be designed in such a manner that it preserves the
historic character of the original structure.
Existing Additions
An existing addition may have taken on historic
significance itself. It may have been constructed to
be compatible with the original building and it may
be associated with the period of historic significance,
thereby meriting preservation in its own right. Such
an addition should be carefully evaluated before
developing plans that may involve its alteration.
In some cases, an early alteration that has taken
on significance actually contrasts with the original
building, for example, a Modernist addition that
was constructed on a Chalet style structure. The
change reflects the evolution of the property. This
type of addition could be significant and worthy of
preservation.
The majority of more recent additions usually have
no historic significance. Some later additions in
fact detract from the character of the building, and
may obscure significant features. Removing such
noncontributing additions is encouraged.
Basic Principles for New Additions
When planning an addition to a historic building,
minimize negative effects to the historic building
fabric. Alterations and additions should reflect their
own time while being subordinate and supportive of
the historic resource.
The addition shall not affect the architectural character
of the building. In most cases, loss of character can
be avoided by locating the addition to the rear. The
overall design of the addition must be in keeping with
the historic structure and be distinguishable from
the historic portion. This philosophy balances new
and old construction and allows the evolution of the
building to be understood.
Keeping the size of the addition small and subordinate,
in relation to the main structure, helps minimize its
visual impacts. An addition must be set apart from
the historic building, and connected with a one story
linking element. This creates a break between new and
old construction and will help maintain the perceived
scale and proportion of the historic resource.
In historic districts, consider the effect the addition
may have on the character of the area, as seen from
the public right-of-way. For example, a side addition
may change the sense of rhythm established by side
yards in the block. Locating the addition to the rear
c HApter 10: building A dditions
Policy: A new addition to a historic building
must be designed such that the character of
the original structure is maintained. It shall
also be subordinate in appearance to the main
building. Previous additions that have taken on
significance must be preserved.
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80 • City of Aspen • Historic Preservation Design Guidelines
cHapter 10: BuIldIng addItIons
would be a better solution in such a case.
When designing an addition to a building, it is also
important to remember that the maximum potential
floor area in the Land Use Code is not guaranteed
if it cannot be appropriately accommodated on
the site. In some cases, smaller additions may be
necessary. Approval for Transferrable Development
Rights may be sought if unbuilt floor area cannot be
accommodated on the site.
Existing Additions
10.1 Preserve an older addition that has
achieved historic significance in its own right.
10.2 A more recent addition that is not
historically significant may be removed.
• For Aspen Victorian properties, HPC generally
relies on the 1904 Sanborn Fire Insurance maps
to determine which portions of a building are
historically significant and must be preserved.
• HPC may insist on the removal of non-historic
construction that is considered to be detrimental
to the historic resource in any case when
preservation benefits or variations are being
approved.
Before: An addition extended the length of the cross gable and
porch on this house, significantly altering its character.
After: The same house after the non-historic addition was
removed and the building was restored using historic photos.
After: The same building after restoration.
Before: Additions on the front of this structure, and an
application of stucco masked the architectural significance of
the building.
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City of Aspen • Historic Preservation Design Guidelines • 81
The rear addition varies from the form of the resource, but
addresses the materiality and fenestration.
New Additions
10.3 Design a new addition such that one’s
ability to interpret the historic character of the
primary building is maintained.
• A new addition must be compatible with the
historic character of the primary building.
• An addition must be subordinate, deferential,
modest, and secondary in comparison to the
architectural character of the primary building.
• An addition that imitates the primary building’s
historic style is not allowed. For example, a new
faux Victorian detailed addition is inappropriate
on an Aspen Victorian home.
• An addition that covers historically significant
features is inappropriate.
• Proposals on corner lots require particular
attention to creating compatibility.
10.4 The historic resource is to be the focus of
the property, the entry point, and the
predominant structure as viewed from the
street.
• The historic resource must be visually dominant
on the site and must be distinguishable against
the addition.
• The total above grade floor area of an addition
may be no more than 100% of the above grade
floor area of the original historic resource. All other
above grade development must be completely
detached. HPC may consider exceptions to this
policy if two or more of the following are met:
• The proposed addition is all one story.
• The footprint of the new addition is closely
related to the footprint of the historic resource
and the proposed design is particularly
sensitive to the scale and proportions of the
historic resource.
• The project involves the demolition
and replacement of an older addition that
is considered to have been particularly
detrimental to the historic resource.
• The interior of the resource is fully utilized,
containing the same number of usable floors
as existed historically.
• The project is on a large lot, allowing the
addition to have a significant setback from the
street.
• There are no variance requests in the
application other than those related to historic
conditions that aren’t being changed.
cHapter 10: BuIldIng addItIons
An addition that does not provide a transition between old and
new, and imitates the original building is no longer allowed.
A side and rear addition that uses materials to differentiate
between new and old construction.
144
82 • City of Aspen • Historic Preservation Design Guidelines
• The project is proposed as part of a voluntary
AspenModern designation, or
• The property is affected by non-preservation
related site specific constraints such as trees
that must be preserved, Environmentally
Sensitive Areas review, etc.
10.5 On a corner lot, no portion of an addition to
a one story historic resource may be more than
one story tall, directly behind that resource,
unless completely detached above grade by a
distance of at least 10 feet
HPC may consider exceptions to this policy if two or
more of the following are met:
• The connector element that links the new and
old construction is a breezeway or transparent
corridor, well recessed from the streetfacing
side(s) of the historic resource and the area of two
story construction that appears directly behind
the one story historic resource is minimal
• The footprint of the new addition is closely related
to the footprint of the historic resource and the
proposed design is particularly sensitive to the
scale and proportions of the historic resource
• The project involves the demolition and
replacement of an older addition that is considered
to have been particularly detrimental to the
historic resource
• The interior of the resource is fully utilized,
containing the same number of usable floors as
existed historically
• There are no variance requests in the application
other than those related to historic conditions that
aren’t being changed
• The project is proposed as part of a voluntary
AspenModern designation, or
• The property is affected by non-preservation
related site specific constraints such as trees that
must be preserved, Environmentally Sensitive
Areas review, etc.
10.6 Design a new addition to be recognized
as a product of its own time.
• An addition shall be distinguishable from the
historic building and still be visually compatible
with historic features.
• A change in setbacks of the addition from the
historic building, a subtle change in material, or
a modern interpretation of a historic style are
all techniques that may be considered to help
define a change from historic construction to new
cHapter 10: BuIldIng addItIons
This addition to this Victorian is clad entirely in brick to
distinguish itself from the original clapboard sided Victorian.
This addition is taller than the resource, but setback on the lot
and scaled in a sympathetic manner.
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City of Aspen • Historic Preservation Design Guidelines • 83
cHapter 10: BuIldIng addItIons
construction.
• Do not reference historic styles that have no basis
in Aspen.
• Consider these three aspects of an addition;
form, materials, and fenestration. An addition
must relate strongly to the historic resource in
at least two of these elements. Departing from
the historic resource in one of these categories
allows for creativity and a contemporary design
response.
• Note that on a corner lot, departing from the form
of the historic resource may not be allowed.
• There is a spectrum of appropriate solutions
to distinguishing new from old portions of a
development. Some resources of particularly
high significance or integrity may not be the right
instance for a contrasting addition.
10.7 When planning an addition to a building in
a historic district, preserve historic alignments
on the street.
• Some roof lines and porch eaves on historic
buildings may align at approximately the same
height. An addition can not be placed in a location
where these relationships would be altered or
obscured.
10.8 Design an addition to be compatible in
size and scale with the main building.
• An addition that is lower than, or similar to the
height of the primary building, is preferred.
10.9 If the addition is taller than a historic
building, set it back from significant façades
and use a “connector” to link it to the historic
building.
• Only a one-story connector is allowed.
• Usable space, including decks, is not allowed
on top of connectors unless the connector has
limited visibility and the deck is shielded with a
solid parapet wall.
• In all cases, the connector must attach to the
historic resource underneath the eave.
• The connector shall be a minimum of 10 feet long
between the addition and the primary building.
• Minimize the width of the connector. Ideally, it
is no more than a passage between the historic
resource and addition. The connector must reveal
the original building corners. The connector may
not be as wide as the historic resource.
The side addition and connecting element on a lot with no
alley use simple forms and contemproary materials. A low
profile flat roof rear addition hides the new construction
behind the landmark.
An addition that uses traditional forms with contemproary
architectural details and materials.
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84 • City of Aspen • Historic Preservation Design Guidelines
cHapter 10: BuIldIng addItIons
• Any street-facing doors installed in the connector
must be minimized in height and width and
accessed by a secondary pathway. See guideline
4.1 for further information.
10.10 Place an addition at the rear of a primary
building or set it back substantially from the
front to minimize the visual impact on the
historic structure and to allow the original
proportions and character to remain prominent.
• Locating an addition at the front of a primary
building is inappropriate.
• Additions to the side of a primary building
are handled on a case-by-case basis and are
approved based on site specific constraints that
restrict rear additions.
• Additional floor area may also be located under
the building in a basement which will not alter the
exterior mass of a building.
10.11 Roof forms shall be compatible with the
historic building.
• A simple roof form that does not compete with the
historic building is appropriate.
• On Aspen Victorian properties, a flat roof may only
be used on an addition to a gable roofed structure
if the addition is entirely one story in height, or if
the flat roofed areas are limited, but the addition is
primarily a pitched roof.
10.12 Design an addition to a historic structure
that does not destroy or obscure historically
important architectural features.
• Loss or alteration of architectural details, cornices,
and eavelines must be avoided.
Rooftop Additions on Flat Roofed
Buildings
10.13 When constructing a rooftop addition,
keep the mass and scale subordinate to that of
the historic building.
10.14 Set a rooftop addition back from the
street facing façades to preserve the original
profile of the historic resource.
• Set the addition back from street facing façades a
distance approximately equal to its height.
10.15 The roof form of a rooftop addition must
be in character with the historic building.
This rooftop addition is subordinate to the architecture of the
original historic resource.
This lot could not accomodate a rear addition. This side addition is
successful because of simplicity, scale & separation.
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City of Aspen • Historic Preservation Design Guidelines • 85
cHapter 11: new BuIldIngs on landMarked propertIes
The City provides several incentives for residential
property owners to divide the square footage that
could be built on a landmark parcel into two or more
separate structures, to reduce the size of an addition
made to a historic house and to reinforce the original
character of many of Aspen’s neighborhoods, which
had small buildings on 3,000 square foot lots. To
determine if a property is eligible for a historic lot split
to subdivide ownership of such structures, refer to the
Aspen Municipal Code.
Designing a new building to fit within the historic
character of a landmarked property requires careful
thought. Preserving a historic property does not
mean it must be “frozen” in time, but it does mean that
a new building should be designed in a manner that
reinforces the basic visual characteristics of the site.
The new building should not look old: imitating historic
styles is inappropriate. It is appropriate to convey
the evolution of the property and neighborhood,
discerning the apparent age of each building by its
style, materials, and method of construction.
A new design must relate to the fundamental
characteristics of the historic resource (site,
location, mass, form, materials, details) and be
“of it’s own time.” For instance, a traditional form
may have contemporary materials and windows
to balance new and old construction. On the other
hand, a contemporary form may have traditional
materials that relate to the resource to maintain a
strong dialogue between new and old construction.
Simplicity and modesty in design are encouraged.
Building Orientation
Aspen Victorian buildings are usually oriented with
the primary entrance facing the street. This helps
establish a pedestrian-friendly quality. AspenModern
buildings have a range of orientations depending on
the design philosophy of the architect. For example, a
Chalet style building is often sited at an angle to face
mountain views.
Building Alignment
A front yard serves as a transitional space between
the public sidewalk and the private building entry. In
many blocks, front yards are similar in depth, resulting
in a relatively uniform alignment of building fronts
which contributes to the sense of visual continuity.
Maintaining the established range of setbacks is
therefore preferred.
Mass and Scale
A new building must be compatible in mass and
scale with its historic neighbor and not overwhelm
it. At the same time, minimizing any addition to the
historic resource and shifting square footage to the
new structure is generally desired.
Building Form
Most historic buildings in Aspen are composed of
simple forms - a simple rectangular solid is typical.
In some cases, a building consists of a combination
of simple forms. A new building should respect these
traditions.
c HA pter 11: n ew b uildings on l A nd MA rked p roperties
Policy: New detached buildings may be
constructed on a parcel that includes a
landmarked structure. It is important that the
new building be compatible and not dominate
the historic structure.
Note: The Residential Design Standards
described in the Aspen Municipal Code apply in
addition to these guidelines.
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86 • City of Aspen • Historic Preservation Design Guidelines
cHapter 11: new BuIldIngs on landMarked propertIes
This new home is strongly related to the scale and forms of the
adjacent Victorian.
This new structure uses Victorian inspired forms and materials,
but a contemporary approach to fenestration.
Building Placement
11.1 Orient the new building to the street.
• Aspen Victorian buildings should be arranged
parallel to the lot lines, maintaining the traditional
grid pattern.
• AspenModern alignments shall be handled case
by case.
• Generally, do not set the new structure forward
of the historic resource. Alignment of their front
setbacks is preferred. An exception may be made
on a corner lot or where a recessed siting for the
new structure is a better preservation outcome.
Mass and Scale
11.2 In a residential context, clearly define the
primary entrance to a new building by using a
front porch.
• The front porch shall be functional, and used as
the means of access to the front door.
• A new porch must be similar in size and shape to
those seen traditionally.
11.3 Construct a new building to appear
similar in scale and proportion with the historic
buildings on a parcel.
• Subdivide larger masses into smaller “modules”
that are similar in size to the historic buildings on
the original site.
• Reflect the heights and proportions that
characterize the historic resource.
11.4 Design a front elevation to be similar in
scale to the historic building.
• The primary plane of the front shall not appear
taller than the historic structure.
11.5 The intent of the historic landmark lot
split is to remove most of the development
potential from the historic resource and place
it in the new structure(s).
• This should be kept in mind when determining how
floor area will be allocated between structures
proposed as part of a lot split.
11.6 Design a new structure to be recognized
as a product of its time.
• Consider these three aspects of a new building;
form, materials, and fenestration. A project
must relate strongly to the historic resource in
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City of Aspen • Historic Preservation Design Guidelines • 87
at least two of these elements. Departing from
the historic resource in one of these categories
allows for creativity and a contemporary design
response.
• When choosing to relate to building form, use
forms that are similar to the historic resource.
• When choosing to relate to materials, use
materials that appear similar in scale and finish to
those used historically on the site and use building
materials that contribute to a traditional sense of
human scale.
• When choosing to relate to fenestration, use
windows and doors that are similar in size and
shape to those of the historic resource.
11.7 The imitation of older historic styles is
discouraged.
• This blurs the distinction between old and new
buildings.
• Overall, details shall be modest in character.
This new home reinterprets the roof form and balcony found
on the Chalet home next door.
The adjacent Chalet.
cHapter 11: new BuIldIngs on landMarked propertIes
150
151
d esign g uidelines : g ener A l
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90 • City of Aspen • Historic Preservation Design Guidelines
cHapter 12: accessIBIlIty, arcHItectural lIgHtIng, MecHanIcal equIpMent, servIces areas, & sIgnage
Accessibility
In 1990, the passage of the Americans with
Disabilities Act (ADA) mandated that all places
of public accommodation be made accessible to
everyone. This includes historic structures that are
used for commercial and multifamily purposes. While
all buildings must comply, alternative measures may
be considered to ensure the integrity of a historic
resource.
Lighting
The character and intensity of outdoor lighting is a
concern in the community. Exterior lighting should be
shielded in keeping with “Dark Skies” inspired policies.
The City of Aspen has lighting standards which must
be met in addition to HPC guidelines.
Mechanical Equipment & Service Areas
New technologies in heating, ventilating and
telecommunications have introduced mechanical
equipment into historic areas where they were not
seen traditionally. The visual impacts of such systems
should be minimized such that one’s ability to perceive
the historic character of the context is maintained.
Locating equipment such that it is screened from
public view is the best approach.
Awnings
Large fabric awnings were common on commercial
buildings in the 19th century, helping to cool the
interior and providing shelter for storefronts. They
are not typical of AspenModern buildings, where a
brise soleil or similar cantilevered element served the
purpose of an awning.
Signs
Signs should not detract from character defining
elements of a historic structure. Where possible,
free standing signs, rather than signs mounted on
buildings are preferred. Sign lighting should be
minimized or concealed. The City of Aspen has a sign
code that must be met in addition to HPC guidelines.
Accessibility
12.1 Address accessibility compliance
requirements while preserving character
defining features of historic buildings and
districts.
• All new construction must comply completely
with the International Building Code (IBC) for
accessibility. Special provisions for historic
buildings exist in the law that allow some
flexibility when designing solutions which meet
accessibility standards.
c HA pter 12: A ccessibility , A rc H itectur A l l ig H ting , M ec HA nic A l e quip M ent , s ervice A re A s , & s ign Age
A subtle ramp eliminates the need for a step onto this historic
porch and therefore meets accessibility requirements.
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City of Aspen • Historic Preservation Design Guidelines • 91
A reconstruction of the original light fixture that once existed
on an AspenModern building.
cHapter 12: accessIBIlIty, arcHItectural lIgHtIng, MecHanIcal equIpMent, servIces areas, & sIgnage
Lighting
12.2 Original light fixtures must be maintained. When there is evidence as to the appearance of original fixtures that are no longer present, a
replication is appropriate.
12.3 Exterior light fixtures should be simple in
character.
• The design of a new fixture should be appropriate
in form, finish, and scale with the structure.
• New fixtures should not reflect a different period
of history than that of the affected building, or be
associated with a different architectural style.
• Lighting should be placed in a manner that is
consistent with the period of the building, and
should not provide a level of illumination that is
out of character.
• One light adjacent to each entry is appropriate
on an Aspen Victorian residential structure. A
recessed fixture, surface mounted light, pendant
or sconce will be considered if suited to the
building type or style.
• On commercial structures and AspenModern
properties, recessed lights and concealed lights
are often most appropriate.
Mechanical Equipment & Service Areas
12.4 Minimize the visual impacts of utilitarian
areas, such as mechanical equipment and
trash storage.
• Place mechanical equipment on the ground where
it can be screened.
• Mechanical equipment may only be mounted on
a building on an alley façade.
• Rooftop mechanical equipment or vents must
be grouped together to minimize their visual
impact. Where rooftop units are visible, it may be
appropriate to provide screening with materials
that are compatible with those of the building
itself. Use the smallest, low profile units available
for the purpose.
• Window air conditioning units are not allowed.
• Minimize the visual impacts of utility connections
and service boxes. Group them in a discrete
location. Use pedestals when possible, rather
than mounting on a historic building.
• Paint mechanical equipment in a neutral color to
minimize their appearance by blending with their
backgrounds
• In general, mechanical equipment should be
A simple sconce is
appropriate for the front door
of this Victorian.
Concealed lighting is
appropriate for this
AspenModern landmark.
Wrightian influenced flush mounted fixtures suit the
Hearthstone Lodge.
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92 • City of Aspen • Historic Preservation Design Guidelines
vented through the roof, rather than a wall, in a
manner that has the least visual impact possible.
• Avoid surface mounted conduit on historic
structures.
Awnings
12.5 Awnings must be functional.
• An awning must project at least 3 feet, and not
more than 5 feet from the building façade.
• An awning may only be installed at a door or
window and must fit within the limits of the door
or window opening.
• Awnings are inappropriate on AspenModern
properties unless historic evidence shows
otherwise.
Signs
12.6 Signs should not obscure or damage
historic building fabric.
• Where possible, install a free standing sign that
is appropriate in height and width. Consolidate
signage for multiple businesses.
• Mount signs so that the attachment point can be
easily repaired when the sign is replaced. Do not
mount signage directly into historic masonry.
• Blade signs or hanging signs are generally
preferred to wall mounted signs because the
number of attachment points may be less.
• Signs should be constructed of wood or metal.
• Pictographic signs are encouraged because they
add visual interest to the street.
12.7 Sign lighting must be subtle and
concealed.
• Pin mounted letters with halo lighting will not be
approved on Aspen Victorian buildings.
• The size of a fixture used to light a sign must be
minimized. The light must be directed towards
the sign. If possible, integrate the lights into the
sign bracket.
12.8 Locate signs to be subordinate to the
building design.
• Signs should be located on the first floor of
buildings, primarily.
• Signs should not obscure historic building
details.
12.9 Preserve historic signs.
cHapter 12: accessIBIlIty, arcHItectural lIgHtIng, MecHanIcal equIpMent, servIces areas, & sIgnage
Historic awnings on Cooper Avenue.
Awnings at the Wheeler Opera House
Historic blade signs.
155
A ppendix
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94 • City of Aspen • Historic Preservation Design Guidelines
appendIx
The Secretary of the
Interiors’ Standards for the
Rehabilitation of Historic
Buildings.
The Secretary of the Interior’s Standards for the
Rehabilitation of Historic Buildings are general
rehabilitation guidelines established by the National
Park Service. Rehabilitation is defined as the act or
process of making possible a compatible use for a
property through repair, alterations, and additions
while preserving those portions or features which
convey its historical, cultural, or architectural values.
These standards are policies that serve as a basis for
the design principles presented in this document. The
Secretary’s Standards state that:
1. A property will be used as it was historically or
be given a new use that requires minimal change
to its distinctive materials, features, spaces, and
spatial relationships.
2. The historic character of a property will be
retained and preserved. The removal of distinctive
materials or alteration of features, spaces, and
spatial relationships that characterize a property
will be avoided.
3. Each property will be recognized as a physical
record of its time, place, and use. Changes that
create a false sense of historical development,
such as adding conjectural features or elements
from other historic properties, will not be
undertaken.
4. Changes to a property that have acquired historic
significance in their own right will be retained and
preserved.
5. Distinctive materials, features, finishes, and
construction techniques or examples of
craftsmanship that characterize a property will be
preserved.
6. Deteriorated historic features will be repaired
rather than replaced. Where the severity of
deterioration requires replacement of a distinctive
feature, the new feature will match the old
in design, color, texture, and, where possible,
materials. Replacement of missing features will
be substantiated by documentary and physical
evidence.
7. Chemical or physical treatments, if appropriate,
will be undertaken using the gentlest means
possible. Treatments that cause damage to
historic materials will not be used.
8. Archeological resources will be protected and
preserved in place. If such resources must be
disturbed, mitigation measures will be undertaken.
9. New additions, exterior alterations, or related
new construction will not destroy historic
materials, features, and spatial relationships that
characterize the property. The new work will be
differentiated from the old and will be compatible
with the historic materials, features, size, scale and
proportion, and massing to protect the integrity of
the property and its environment.
10. New additions and adjacent or related new
construction will be undertaken in such a manner
that, if removed in the future, the essential form
and integrity of the historic property and its
environment would be unimpaired.
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City of Aspen • Historic Preservation Design Guidelines • 95158