2021 IECC
New residential structures of any size:
For permit submittals… Prescriptive, Total UA and the Performance Paths have been deleted. Projects must use the ERI compliance path. Since the 2021 ERI capped solar PV intervention at 5%, HERS Ratings are now accepted in lieu of ERI’s. Projects must show a HERS of 60 before photovoltaic solar energy is applied, and HERS 30 afterwards.
Additions, remodels, and heated accessory structures:
For permit submittals…
Option 1 Prescriptive Modified table 402.1.2 from the 2021 IECC including U-factors of .28 for exterior glazing and .40 for skylights (and better) or a weighted average meeting those values.
Option 2 Total UA Passing a 2021 ResCheck (Total Building UA Calculation) using glazing U-factors of .28 for exterior glazing, .40 for skylights, and continuous exterior insulation.
Continuous exterior insulation requirement may be waived if proven non-feasible, existing exterior wall assemblies remain unchanged or existing siding remains unchanged.
Option 3 HERS rating of 53 from table R406.4 in the 2015 IECC
Commercial buildings:
Building thermal envelope -2021 IECC prescriptive table or pass a 2021 ComCheck thermal envelope compliance report.
Lighting -Pass a 2021 ComCheck Interior and exterior lighting compliance report.
Mechanical -Pass a 2021 ComCheck mechanical compliance report.
REMP, CREMP & GREMP
Renewable Energy Mitigation Program (REMP) payment option is voluntary. Applicants interested in exterior energy use systems can alternatively choose to produce on-site renewable energy (Section 301) with solar photovoltaics and/or solar hot water, ground-source heat pumps or micro-hydro. Download Pitkin County REMP Calculation Sheet
Confluence Architecture & Sustainability can help with REMP calculations and provide all the documentation, modeling, testing and certification required to navigate the code.