Low slope - CalGreen

Low slope – CalGreen


CalGreen or California Green Building Standards Code is the 11th of 12 parts of Title 24, also referred to as the California Building Standards Code. Installing a cool roof is one of the measures included for the additional voluntary tiers that a city or community could adopt beyond the mandatory code. The CALGreen Tier 1 & Tier 2 voluntary energy efficiency measures are designed to exceed the 2008 energy efficiency standards (Title 24) by 15% or 30%. Cool roof requirements vary depending on climate zones; therefore, be sure to know in which climate zone you are located.

Find out specific building code requirements for your area.


Cool roof requirements for many of the building codes and standards vary depending on climate zones. You can reference the following maps to find your climate zone.  Also, check out California Energy Commission's website to locate your climate zone by cities/towns or zip code.

California Building Climate Zones (for California Building Standards Code)

CA Climate Zones

California’s 16 building climate zones

Image source: LBNL – Heat Island Group