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🌡️ Climate Zoneconstruction

IECC Climate Zone 3 — Warm

Updated Mar 26, 2026
Mixed climate zone spanning mid-South, California coast, and parts of Southwest. Both heating and cooling significant. Code addresses both solar gain control and insulation levels.
TAGS
IECCwarmmixedCaliforniaSoutheast
DETAILS
hdd range
3,000-4,000
iecc zone
3
example cities
Los Angeles, Atlanta, Dallas, Memphis, Las Vegas, Raleigh
roof insulation
R-38 to R-60
wall insulation
R-13+R-5ci or R-20+R-3ci
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