Fontana Climate Zone & Energy Code

Climate Zone: CEC Climate Zone 10 (central Inland Empire / San Bernardino County). IECC Climate Zone 3B. Fontana's valley floor position is among the hottest in the Inland Empire — 103°F cooling design and 28°F heating design. The flat terrain provides no mountain moderation available in foothill communities.

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 Fontana and San Bernardino County jurisdictions enforce Title 24.

Local Electric Utility: Southern California Edison (SCE)

Building Department: City of Fontana Building & Safety Department

Local Trade Association: ACCA California