California Building Climate Zone
California spans hot dry, marine, and colder mountain climate zones. State-level climate-zone pages are planning baselines; IECC climate zones are county based.
Planning baseline
- IECC climate zone: Zone 3B
- Climate type: Warm mixed
- Wall planning target: R-20 or R-13 + R-5 continuous insulation
- Attic planning target: R-49 to R-60
- Floor planning target: R-19