Simi Valley Climate Zone & Energy Code

Climate Zone: CEC Climate Zone 9 (east Ventura County / Simi Valley). IECC Climate Zone 3B. Simi Valley's enclosed valley position produces warmer summer conditions than coastal Ventura County — 97°F cooling design — with Santa Ana events pushing temperatures higher. Heating design 30°F.

Energy Code & Manual J Requirement: California Title 24 Part 6 (2025 edition, effective January 1, 2026). ACCA Manual J required for residential HVAC sizing. All Simi Valley and Ventura County jurisdictions enforce Title 24.

Local Electric Utility: Southern California Edison (SCE)

Building Department: City of Simi Valley Building & Safety Division

Local Trade Association: ACCA California