DOE Climate Zone Map: 8 zones (1 hot-humid to 8 subarctic), moisture suffix (A moist, B dry, C marine)
IECC R-value (DOE climate-zone) — Climate Zone MapDescription
The DOE Building America climate-zone map divides the US into 8 thermal zones (1 = warmest, 8 = coldest) overlaid with a moisture regime: A (moist), B (dry), or C (marine). Most of NY is Climate Zone 4A (mixed-humid) in the south + 5A (cold) in the north + 6A (cold) in the high Adirondacks. Climate zone drives every envelope R-value, window U-factor, and vapor-retarder requirement in the energy code.
Why this exists
Climate zone is the architect's foundational design parameter — picked first, dictates the whole envelope strategy. Architects should pull the project's climate zone from the IECC adoption map (or DOE map) at project start, NOT improvise from intuition. Energy modeling tools default to it.
Categories
Source
Solver enforcement
Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.
Related directives
- Floodplain construction · IRC R301.2.4
- Whole-dwelling mechanical ventilation rate · IRC R303.4
- Required heating · IRC R303.8
- Lowest-floor elevation in flood-hazard areas · IRC R322.2
- EV charging systems must be installed per NFPA 70 with disconnecting means per FC NY §611 · 2025 RCNYS §R317.6 Electric vehicle charging
Last reviewed 2026-05-15.