To standardize calculations and provide a basis for presenting the prescriptive
requirements, the Energy Commission has established a set of standard climate data for
each of the 16 climate zones. The climate zone definitions and data are the same for both the low-rise residential and the non-residential standards.

Beginning with the 2013 Energy Standards, ZIP code boundaries have been used to define
climate zone boundaries; under these rules, a given ZIP code is always located entirely
within a single climate zone.

Go to the link below to find out your climate zone based on your zip code.

https://www.energy.ca.gov/maps/renewable/BuildingClimateZonesByZIPCode.pdf

 (Excerpted from CEC Title-24 Part 6 Residential Compliance Manual)