Nebraska Energy Code Compliance Calculator — Insulation & HVAC Minimums by Climate Zone
Verify that your building's insulation R-values and HVAC equipment efficiencies meet Nebraska's adopted energy code (IECC 2021) requirements for Climate Zones 5A and 6A.
Compliance Logic & Formulas
Each component is checked against IECC 2021 minimum R-values and HVAC efficiency ratings:
- Insulation Pass: Proposed R-Value ≥ Minimum R-Value (per IECC 2021 Table R402.1.2 for residential; Table C402.1.3 for commercial)
- HVAC Pass: Proposed Efficiency ≥ Federal/IECC Minimum (AFUE %, SEER2, HSPF2)
- Overall Compliance: ALL individual checks must pass
- Gap Calculation: Δ = Proposed Value − Minimum Required Value (negative = non-compliant)
Nebraska Climate Zones (IECC 2021 Figure R301.1):
- Zone 5A: Eastern & Central Nebraska — Lincoln, Omaha, Grand Island, Norfolk, Hastings, Kearney
- Zone 6A: Western Nebraska / Panhandle — North Platte, Alliance, Scottsbluff, Valentine, Chadron
Assumptions & References
- Based on IECC 2021 (International Energy Conservation Code), adopted as Nebraska's statewide energy code baseline.
- Residential insulation minimums from IECC 2021 Table R402.1.2 (Insulation and Fenestration Requirements by Component).
- Commercial insulation minimums from IECC 2021 Table C402.1.3 (Opaque Thermal Envelope Insulation Component Minimum Requirements).
- HVAC efficiency minimums reflect U.S. DOE 2023 federal standards for the Northern region (applicable to Nebraska): SEER2 ≥ 13.4 (AC), SEER2 ≥ 14.3 (HP), HSPF2 ≥ 7.5 (HP), AFUE ≥ 80% (furnace), AFUE ≥ 82% (boiler).