HomeMy WebLinkAboutagenda.council.worksession.20250929AGENDA
CITY COUNCIL WORK SESSION
September 29, 2025
4:15 PM, City Council Chambers
427 Rio Grande Place, Aspen
I.Work Session
I.A Board and Commission Interviews
I.B Building Electrification Code Updates
II.Council discussion of the items published in the most recent information update,
as needed
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Board Commission Interviews MEMO - 9-29-25.pdf
Building_Electrification_Code_Updates_-_Work_Session_9.29.2025_FINAL.pdf
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Electrification Work Session
September 29, 2025
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MEMORANDUM
TO: Aspen City Council
FROM: Bonnie Muhigirwa, Chief Building Official
Tessa Schreiner, Environmental Health & Sustainability Manager
Clare McLaughlin, Sustainability Manager
Hailey Roedel, Deputy City Engineer
Erin Loughlin Molliconi, Director of Utilities
THROUGH: Ben Anderson, Community Development Director
Tyler Christoff, Deputy City Manager
MEMO DATE: September 22, 2025
MEETING DATE: September 29, 2025
RE: Building Electrification Code Updates
_____________________________________________________________________
REQUEST OF COUNCIL: This work session’s purpose is to arrive at Council direction
for the creation of possible amendments to city code regarding electrification of the built
environment. These potential amendments could touch several areas within Aspen’s
municipal code. Staff’s engagement on these topics is pursuing three outcomes:
• Continuing to deliver on Council’s previously established science-based
greenhouse gas emissions reductions.
• Setting up Aspen for compliance with State of Colorado requirements for
amendments to building and energy codes that are anticipated to come into effect
in 2026.
• Responding to customer desires in both commercial and residential properties to
pursue electrification for their mechanical systems.
With direction on a series of specific policy questions for Council, staff will return later in
2025 and 2026 with proposed changes to relevant sections of Aspen’s Municipal Code.
These policy questions are categorized into two related topics with background
information and potential solutions that staff could bring back to Council for further review:
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1) Removing barriers to electrification in existing City code
• Height and setbacks related to energy efficient and/or electric mechanical
equipment.
• Site planning requirements to better fit electric equipment space needs
• Potential uses of the Right-of-Way (ROW) for locating new or additional
transformers in certain circumstances.
2) Preparing for state building and energy code updates in 2026 for both new and existing
buildings
• Electric-ready state minimum code requirements or alternative electric codes for
new construction
• Limits for electric capacity in residential buildings and further limits on exterior
energy use.
• Meeting state code minimum requirements for major renovations or above state
minimum codes.
At the conclusion of this memo and as the focus of the work session discussion are
specific questions that Council will be asked to guide staff’s future work in this area.
SUMMARY AND BACKGROUND:
Why Electrification Matters:
• Buildings account for the largest portion of the Aspen community’s emissions, at
47%. Aspen Utilities’ electric grid has been 100% renewable since 2015, and Holy
Cross Energy will provide 100% renewable energy by 2030 and has already
achieved over 80% renewable energy as of 2025. Thus, most emissions from the
built environment, by 2030, will be from gas equipment.
• This provides a unique opportunity for the Aspen community to reach emissions
goals in the built environment by incrementally converting gas mechanical
equipment and appliances to electric equipment.
• In addition, builders, tenants, and property owners are voluntarily and increasingly
choosing to go all-electric.
Previous Council Direction:
• Aspen’s Science-based Targets. In January 2022, Aspen City Council signed on
to Race to Zero and adopted new science-based targets, or greenhouse gas
emissions reduction goals, that reflect Aspen’s fair share of global greenhouse gas
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emissions needed to keep global heating below 1.5 degrees Celsius. These
targets use 2017 as the baseline year and are 63.4% reduction by 2030 and 100%
reduction by 2050
• Aspen Sustainability Action Plan (ASAP). In February 2023, Council approved
the updated Aspen Sustainability Action Plan that includes objectives and action
items specific to supporting and incentivizing building electrification. The plan has
been updated annually since 2023.
• Electrification Task Force. In January 2023, as part of the 2021 building and
energy code adoption, Council directed staff to create an Electrification Task
Force, whose charge is to research and provide recommendations for a
comprehensive building electrification roadmap. Council also directed staff to
come back with energy code updates on a 3-year cycle, which would fall in 2026.
• Building IQ. In April 2022, Aspen City Council passed the Building IQ ordinance.
This addresses emissions from existing buildings in a two-phased approach:
benchmarking and developing a building performance standard for Council
consideration. Building IQ overlaps with electrification in multiple ways, but
electrification itself is a standalone topic, as many of the questions for Council
today are a precursor to considering a building performance standard.
Additional Relevant Background:
• 2025-2027 Council Goals and Principles. This work to proactively remove
barriers to electrification in the community hits on two council goal principles:
Improvement of core service delivery through process improvement with the
customer in mind and outcome focus. It is also relevant to Council’s resource and
infrastructure resilience goal.
• Colorado State Code changes: Under state law, cities and counties with building
codes must adopt the 2021 IECC along with the model electric ready and solar
ready code when adopting or updating any building code between July 1, 2023,
and June 30, 2026. Aspen adopted the 2021 IECC January 24, 2023, but has not
adopted the model electric ready and solar ready code. Beginning July 1, 2026,
any building and energy code adoption in Colorado must meet or exceed the
Colorado Low Energy and Carbon Code and the Electric and Solar Ready Code,
which is based on the 2024 IECC.
• Community demand: Community members, businesses, and builders have
already demonstrated market interest in building electric or partially electric
buildings. In addition, staff and community members have identified various areas
where current city code presents barriers to voluntarily developing electric or
partially electric buildings.
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In summary, current city code presents barriers to electrification, yet for the City to honor
its commitments and goals, meet state codes, and address community needs, a pathway
to electrification is imperative.
DISCUSSION:
Over the last year, through the work of the Council-directed Electrification Task Force,
stakeholder and customer feedback, and a cross-departmental team with representation
from Engineering, Utilities, Planning, Building, Environmental Health and Sustainability,
and Parks, City staff have aligned on several key policy questions for Council on
electrification, categorized into two topics:
1. Removing barriers to electrification in existing City code, and
2. Preparing to meet or exceed state building and energy code updates in 2026 for
new and renovations to existing buildings
The section below includes policy questions for Council consideration to provide context
for solutions that staff could bring to Council with further detail in future meetings.
1. Removing barriers to electrification in existing City code
Policy Question 1: Is Council supportive of adjusting height and setback
restrictions to accommodate high efficiency electric equipment?
• Background: Equipment, including electric equipment such as heat pumps,
is getting larger, and current code is restrictive for this type of equipment.
Due to Aspen’s tight lots, setbacks and roofs are often the only remaining
area to put equipment.
• Potential solutions for future review:
o Provide greater allowances in setbacks for equipment enabling
electrification in existing buildings.
o Provide height allowance for equipment enabling electrification in
new buildings and in major renovations to existing buildings.
o Require new buildings to locate equipment outside of setbacks.
Policy Question 2: Is Council supportive of changing site planning requirements to
better fit electric equipment space needs?
• Background: New buildings do not always plan for adequate space on
property for mechanical equipment resulting in more equipment located in
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setbacks. Existing buildings often have site constraints and will need
additional flexibility.
• Potential solution for future review:
o Require new construction to allocate space for mechanical
equipment on property with minimum or no use of setbacks as a
foundation to the planning process.
o Create new standards and potential for flexibility for existing
development.
Policy Question 3: Is Council supportive of allowing transformers to be placed in
the right-of-way (ROW) in certain circumstances?
• Background: Increased electric demand will most likely require larger
capacity and/or additional transformers. The number of physical
connections available for customer service in each transformer is limited. In
cases where there are no more available connections in a transformer, an
additional transformer would be necessary to serve the increased electric
demand. For some existing buildings, there is insufficient space to support
additional transformers on property. Current Aspen Engineering Standards
do not allow transformers in the ROW. Locating transformers in the ROW
has the tradeoff of impeding current or hindering future development of
pedestrian, bicycle, and utility corridors.
• Potential solutions for future review:
o Require new construction to locate transformers outside the ROW
o Allow transformers in the ROW for existing buildings in some
circumstances via an approved variance to engineering standards
2. Preparing for state building and energy code updates in 2026 for both new and
existing buildings
Background on State code requirements and timeline
State law requires the City to adopt building codes that are at least as stringent as state
model codes. Currently, there are two model codes: the Model Electric and Solar Ready
Code (effective until June 1, 2026) and the Low Energy and Carbon Model Code, which
becomes the standard thereafter. Without modifications, adopting the state model codes
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presents implementation challenges in Aspen and falls short of meeting the City’s climate
goals.
The state codes mandate that all new buildings install infrastructure as if the building were
to be all-electric (electric-ready). This requires installing sufficient panel capacity, space,
and pre-wiring for electric systems like heating, cooking, and drying. In Aspen, this could
lead to significant increases in electric infrastructure for all building types, especially in
single-family homes with luxury features (see Policy Question 5 for impacts on the electric
distribution system).
Moreover, since the model codes require infrastructure but not electric equipment, they
do not directly reduce emissions. Installing electric systems would cut building-related
emissions thanks to Aspen Electric’s 100% renewable energy. Infrastructure alone adds
embodied carbon and cost, without ensuring a shift to electric equipment or actual
emissions reductions.
In summary, the City can either adopt the State’s model codes or pursue modified codes
that meet state code minimums while addressing Aspen’s unique built environment.
Council direction on the policy questions below will guide staff on which code options to
bring back to Council for detailed consideration.
A. Policy questions for new construction
Policy Question 4: Is Council supportive of pursuing an all-electric code for new
construction?
• Background: Requiring new construction to be all-electric will have the
greatest impact on lowering Aspen’s emissions in the built environment.
Comparatively, the state electric ready code will have large and expensive
impacts to buildings and the grid, presenting barriers to implementation,
without reducing emissions in the near term. City staff have been
investigating the challenges around building electrification for several years
and while it will require design changes and application of new technology,
it is achievable, particularly if the City addresses the code conflicts outlined
in topic 1 (above).
• Potential solutions for future review:
o Require new buildings to be all-electric, which could include
exceptions for cooking, fireplaces and emergency generators.
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o Pursue an electric-preferred code, which would allow gas but apply
additional requirements to buildings with gas to encourage all-
electric construction.
Policy Question 5: Is Council supportive of limiting electric capacity for residential
buildings (and should options include further limits on exterior energy use)?
• Background: All-electric buildings and even electric-ready buildings (which
would be required by the State’s model code) often require larger service
sizes (demonstrated through a recent study with Pitkin County). This is
compounded in Aspen’s context due to significant electric demands for
amenities in large luxury homes. The growing electric demand driven by
electrification and continued development will have implications for Aspen
Electric’s infrastructure and operations.
One implication of larger service sizes for all-electric or electric-ready
customers is the need for larger and/or additional transformers (see Policy
Question 3). Another implication is oversizing transformers to meet all-
electric demands, which have not been optimized to consider non-
concurrent demands, or to meet future all-electric loads as required in the
electric-ready code. This could have the effect of obligating infrastructure
and system capacity to an unused or future load, which could impact the
distribution system’s electrical line losses, particularly when considered at
a system-wide scale, due to continuous standby energy consumption.
• Potential solutions for future review:
o Pursue a residential electric capacity limit. The water utility has set
a potential precedent for this with the single-family residential
equivalent capacity unit (ECU) cap. An electric capacity limit would
help mitigate the impacts and challenges of building electrification.
Exploring different energy capacity limits for all-electric or electric-
ready buildings could be a way to incentivize efficient, electric
buildings. This could be explored in an all-electric code or as part of
an electric-preferred code that incentivizes electrification.
o Set a limit on service size based on house size or another metric
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B. Policy questions for major renovations
Policy Question 6: Does Council want to meet the state code minimum for major
renovations or pursue above state minimum codes?
• Background: Existing buildings pose additional challenges because it can
be complex to convert existing gas heating systems and space for new
equipment is often limited. The state electric-ready code requirements apply
to major renovations, and jurisdictions can set their own definition for a
major renovation. The vast majority of development in Aspen involves
renovations to existing buildings, and facilitating their move to fully or
partially electric heating and cooling systems will have a significant impact
on reducing emissions.
• Potential solutions for future review:
o Electric-ready requirements for major renovations (state minimum)
o Partial-electrification option for major renovations to electrify the
biggest end uses with existing gas systems as back up.
FINANCIAL IMPACTS:
While pursuing policy and code changes have and will incur the expense of staff time, the
main financial considerations are for the costs associated with the development and
operations of new and existing buildings.
Electrification of buildings can be a more expensive alternative than fossil-fuel appliances
in some circumstances due to infrastructure upgrades, appliance cost, and delivery cost
of electricity versus gas. A separate information-only memorandum on industry drivers,
including the state all-electric code and Clean Energy Plan, affecting the city’s electric
wholesale purchase power has been included in the packet for the September 30th
Regular Meeting.
The City of Aspen has processed multiple projects which have considered all-electric
designs and encountered code conflicts inhibiting such design choices. Resolution of
these code conflicts will lower the financial impacts by avoiding challenging workarounds
and limits on equipment choice. Some studies show all-electric new construction is less
expensive than that of a building using gas systems (source: Eagle County Energy Code
Modeling Report). Financial impacts may be greater for single family homes or
commercial buildings with a large amount of luxury amenities, including exterior energy
systems. Colorado’s minimum electric-ready standard requires all new buildings install
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electrical infrastructure as if the building was to be “all-electric.” Under these conditions,
the addition of gas infrastructure would be unnecessary and add costs to the project.
Electrification of existing buildings, if selecting high-efficiency all-electric equipment
designed for Aspen’s climate, can be more expensive than replacing like-for-like natural
gas equipment. However, Colorado’s minimum standard requires Aspen to apply the
model electric readiness provisions to “major renovations.” In such cases, exceeding
those baseline code standards to require electrification of a portion of space and water
heating systems, while enabling fossil gas systems to stay in place for resilience, can
offer a more cost friendly approach.
Carbon pollution from building energy use imposes a societal cost that should be
considered in decision-making. This metric captures “a variety of negative economic
effects to the world and the national economy, including Colorado. Examples include
costs of flood prevention and mitigation, health care costs associated with excessive heat,
and fire prevention, control, and damages.” The State of Colorado uses a Social Cost of
Carbon (SCC) metric to embed the societal cost of emitting carbon pollution into
transportation planning per Colorado Senate Bill (SB) 21-260 (source: Colorado
Department of Transportation Social Cost of Carbon Analysis Guidance). Using the figure
the State set for 2025, the SCC is $60/ton of carbon dioxide equivalent.
Recognizing that the City of Aspen’s municipal electric grid is powered by 100%
renewable energy, there are no carbon emissions from the use of electricity in electrical
equipment in the City of Aspen. Therefore, there is no associated social cost to all-electric
buildings. Conversely, fossil gas systems release carbon pollution at a consistent rate
when burning fossil gas for their operation. The carbon pollution released from these
systems has an associated social cost that could be calculated on a per building or
community-wide scale.
ENVIRONMENTAL IMPACTS:
Encouraging and expanding building electrification would have the single biggest impact
in meeting the City’s GHG goals. Buildings emit 47% of Aspen’s GHG emissions; with
Aspen Electric’s 100% renewable energy and Holy Cross Energy’s 100% renewable
energy by 2030, electrification is the next step to reduce emissions from this sector.
Electrification of buildings has co-benefits to the environment and community including
improved air quality and public health and increased comfort in the spaces where
community members live, work, and play.
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ALTERNATIVES:
Meeting future State of Colorado building and energy code requirements will be
necessary, but other aspects of Aspen’s efforts to transition to electrification of the built
environment could be slowed or paused.
RECOMMENDATIONS: Staff requests Council direction on the following policy
questions:
1. Removing barriers to electrification in existing City code.
• Policy Question 1: Is Council supportive of adjusting height and setback
restrictions to accommodate high efficiency electric equipment
• Policy Question 2: Is Council supportive of changing site planning
requirements to better fit electric equipment space needs?
• Policy Question 3: Is Council supportive of allowing transformers to be placed
in the right-of-way (ROW) in certain circumstances?
2. Preparing for state building and energy code updates in 2026 for both new and
existing buildings
• Policy Question 4: Is Council supportive of pursuing an all-electric code for
new construction?
• Policy Question 5: Is Council supportive of limiting electric capacity for
residential buildings (and should options include further limits on exterior
energy use)?
• Policy Question 6: Does Council want to meet the state code minimum for
major renovations or pursue above state minimum codes?
CITY MANAGER COMMENTS:
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