Aspen’s adoption of the 2021 I-codes is heavily modified. This article looks only at the energy conservation parts of the adoption. And this is just a summary of the most perennate changes that may influence design.
Link here to the actual adoption documents…
Four compliance paths:
- Prescriptive/Building UA/R-value alternative +23% including all additional mandatory requirements
- Performance +5%
- ERI +5% (2021 ERI 50.35)
- Existing building, Chapter 5
Notable modifications to mandatory residential energy requirements:
- Prescriptive envelope requirements: R60 roof, R40 walls, R20 basement walls, windows max U-factor of .26 (inert gas with uncapped breather tube units don’t count)
- Max 30% glazing to wall area (garage and sunroom glazing counts)
- 1.5 ACH50 air leakage
- ERV/HRV and flow testing required
- Duct leakage testing was stricken for the Prescriptive path
- Special provisions to avoid Thermal bridging
- Commissioning
- Sign Up for Building IQ benchmarking program (data gathering)
- Sensible electric ready provisions
- New triggers for energy efficiency requirements for alterations
Commercial Energy Changes:
- Prescriptive, 2019 ASHRAE 90.1 or Performance
- Envelope infiltration testing; Dwelling and sleeping units .30 CFM50 per square foot of envelope, everything else .40 CFM75 per square foot of envelope.
- ventilation flow testing
- Enhanced envelope, especially walls
- EV requirements
- Electric ready provisions
- New triggers for energy efficiency requirements for alterations
Expanded REMP:
- Heat tape, gas fireplaces, outdoor heaters will now need to be offset
- Gas fireplaces will be required to be sealed combustion
- 200,000,000 BTU/year cap for all exterior energy
- Snowmelt 2414 ft2 OR,
- Pool 603 ft2 OR,
- Spa 466 ft2 OR,
- Heat tape 3125 linear feet of typical heat tape
Incentivize All-Electric New Construction:
- Expedited Permit Review
- AC units must be heat pumps
A practical example:
What if a project needs to break with the Prescriptive path? For instance, how can a house go about complying with more than 30% glazing? The project would be forced to try and comply by using either the Performance Path or the ERI (Energy Rating Index) Path.
Minimum Performance goal would be… 2021 Building UA +23% & 72% of Energy costs
Minimum ERI goal would be… 2021 Building UA +15 % & ERI 50.35 – PV
Both of these goals would have to be achieved without help from PV solar.
We do that…
Please give us a call and we can help navigate the process in the most cost-effective way. And optimize your construction for performance.
Jump to Energy Conservation Code Hub for; the western slope of Colorado; Aspen, Telluride, Mountain Village, Town of Snowmass Village, Basalt, Carbondale, Glenwood Springs, Pitkin and Eagle County…