Spray Foam and Insulation Marketing in California

Climate zones across California

Climate zone shapes what insulation work homeowners ask about, so it shapes what a contractor should lead with. The number rises as the climate gets colder (1 is hot, 8 is subarctic). The letter shows moisture: A is humid, B is dry and C is marine. California has 58 counties in 7 zones.

Source: U.S. DOE and PNNL, Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates (PNNL-33270). As of October 21, 2022.