Type a California ZIP code to find its Title 24 climate zone (CZ1–CZ16) and
jump straight to the prescriptive baseline for that zone. Free, no signup.
By ZIP code
By region
How the lookup works
The California Energy Commission publishes a ZIP-code-to-climate-zone
map; we mirror that data and resolve your ZIP to one of the 16 California
climate zones in real time. The result includes a link to the prescriptive
baseline page for that zone, wall and ceiling R-values, window U-factor
and SHGC, HVAC efficiency, and required water-heater type.
Why your ZIP code matters
Every Title 24 prescriptive value changes by climate zone. Two homes 50
miles apart in California can have entirely different code-minimum specs
for windows, insulation, and HVAC. Knowing the zone before you start the
compliance process saves you from over- or under-specifying equipment. See
the climate zones overview for what
changes between them.
