San Diego Climate Zone & Energy Code
Climate Zone: Multiple CEC climate zones from Zone 7 (coastal marine) through Zone 10 (inland valley) to Zone 15 (Borrego Springs desert). IECC Climate Zone 3B for inland areas. San Diego County's climate diversity is among the greatest of any US county.
Energy Code & Manual J Requirement: California Title 24 Part 6 (2025 edition, effective January 1, 2026). ACCA Manual J required for residential HVAC sizing. San Diego County and all cities enforce Title 24. Military installation construction may follow federal energy codes, but private residential construction on or near installations follows Title 24.
Local Electric Utility: San Diego Gas & Electric (SDG&E)
Building Department: City of San Diego Development Services Department
Local Trade Association: ACCA California / ASHRAE San Diego Chapter / SMACNA San Diego