Aspen council weighs code changes to ease building electrification, flagging setbacks, transformers and service limits

City staff on Monday presented a suite of potential amendments to Aspen’s municipal codes aimed at making it easier for buildings to switch from gas to electricity — and asked the City Council for high‑level direction before drafting detailed ordinances.

Tessa Schreiner, the city’s environmental health and sustainability manager, told council the work responds to three drivers: community feedback that current rules block voluntary electrification, council climate goals, and upcoming Colorado state code changes. "The request of council this evening ... is to arrive at council direction for the creation of possible amendments to city code regarding the electrification of the built environment," Schreiner said.

Why it matters: staff said roughly 47% of Aspen’s community greenhouse‑gas emissions come from the built environment and that replacing gas appliances with electric systems offers a major emissions opportunity because Aspen’s two electric utilities will be fully renewable (Aspen Electric since 2015; Holy Cross Electric by 2030). But staff cautioned that new electric equipment — notably high‑efficiency heat pumps — is often taller and bulkier than older equipment and that code rules on rooftop height (currently a 72‑inch roof equipment limit) and setback requirements frequently force costly workarounds.

Key policy questions and council reaction

Height and setbacks: staff asked whether council supports adjusting roof and setback limits to accommodate taller equipment. Council members generally supported studying targeted flexibility but urged protections for neighbors and historic properties. Bill (Councilmember) urged separate treatment for rooftop versus on‑grade equipment and for stronger, durable screening: "Our screening requirements and strategies have not been successful to date," he said. Schreiner and Ben Anderson, the community development director, acknowledged tradeoffs including noise and visibility and said staff will return with options that differentiate new construction from existing buildings.

Site planning: staff recommended requiring new and substantially redeveloped projects to reserve space for mechanical equipment so installations don’t end up in setbacks or on neighboring lots. Several council members said the concept merits further detail and outreach to architects and developers to ensure it fits Aspen’s lot‑size context.

Transformers in the right of way: developers told staff transformer siting is one of their biggest obstacles. Utilities director Erin Laughlin explained existing standards require pad‑mounted transformers with clearance requirements (three feet at sides and back, ten feet in front) and that some transformer capacity increases can be accommodated on existing vault footprints. Council asked whether, in limited circumstances, transformers could be sited in non‑driving right of way (trails or alleys) or be sub‑graded; Laughlin noted alleys that carry traffic are unlikely candidates but agreed staff will examine other options.

Cost allocation and equity: several council members raised equity concerns that the first property to trigger an upsized transformer can bear the full upgrade cost even though the transformer may serve neighboring properties in future. Bill said that arrangement feels unfair and asked staff to examine cost‑sharing mechanisms.

Service capacity limits: the electrification task force proposed exploring limits on residential electric service (panel) sizes to prevent widespread oversizing of transformers and inefficiencies. The council debate was sharp: some members supported studying modest limits and robust outreach; others called hard caps ‘‘bonkers’’ and warned of medical and practical exceptions and the risk of unintended consequences. Staff said limits would target extreme high‑end loads rather than typical homes and emphasized that Aspen already uses some utility caps for exterior energy in other programs.

Existing buildings and major renovations: staff asked whether major renovations should require more than the state minimum 'electric‑ready' standard. Staff suggested options including "partial electrification" (electrifying the majority of heating/cooling loads — for example 80–90% — while retaining some existing systems as backup). Council asked for clearer thresholds and scenario analyses because some large commercial renovations (including examples such as the Wheeler Opera House) may not be feasible to fully electrify.

Next steps: staff said they will return with detailed code options, technical analysis (including maps and transformer inventories), and extensive stakeholder outreach over the coming year. "With the guidance you've provided tonight, we will circle our subject matter experts, do more in‑depth outreach and over the next year bring back policy options for council to consider," Schreiner said.

What was not decided: Council provided direction to continue research and outreach; no ordinances, motions or votes were taken at the work session.

Context and clarifying details: staff cited that Aspen Electric has been fully renewable since 2015 and that Holy Cross Electric is expected to be fully renewable by 2030. Staff reported the city currently has 264 transformers on its system and that manufacturer's specifications often require heat‑pump equipment to be above grade and taller than Aspen's existing 72‑inch roof limit. Staff flagged a state code timeline: if the city waits past mid‑2026 it would need to adopt the state's 2024 Colorado Low Energy and Carbon Code, the state's version of the 2024 IECC, and noted the state minimum is 'electric‑ready.'

Council asked staff to return with more precise options, cost and equity analysis, and sample scenarios showing how thresholds would apply to a range of buildings. The next formal step will be staff outreach and drafting ordinance language for Planning & Zoning and Historic Preservation Committee review before any council vote.