California Building Climate Zones
The California Energy Code divides the state into 16 building climate zones. Yours is set by project location, and it changes what the code requires.
Climate zones group areas with similar heating and cooling demands so that requirements can be tuned to local conditions. They do not follow city or county lines, and a single ZIP code can span more than one — in which case the local jurisdiction may designate which applies.
Why the zone matters
Envelope and fenestration requirements vary by zone, and under the performance compliance approach the energy budget your design is measured against is itself zone-specific. The same building can comply in one zone and fail in another.
Find your zone
The California Energy Commission publishes an official lookup tool and a ZIP-code list. Look up your climate zone — or simply give us the project address and we will determine it for you.
All 16 zones
- Climate Zone 1
- Climate Zone 2
- Climate Zone 3
- Climate Zone 4
- Climate Zone 5
- Climate Zone 6
- Climate Zone 7
- Climate Zone 8
- Climate Zone 9
- Climate Zone 10
- Climate Zone 11
- Climate Zone 12
- Climate Zone 13
- Climate Zone 14
- Climate Zone 15
- Climate Zone 16
Frequently Asked Questions
Sixteen building climate zones are defined in the California Energy Code.
By the project location. The California Energy Commission publishes an official lookup tool and a ZIP-code list.
Yes, in all 16 California climate zones.