Riverside Climate Zone & Energy Code

Climate Zone: CEC Climate Zone 10 (inland Southern California transition zone). IECC Climate Zone 3B (hot-dry). Riverside's hot, dry summer and relatively cold winters create significant both-season HVAC demand — making accurate load calculation for both cooling and heating important for proper equipment sizing.

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 Riverside County jurisdictions enforce Title 24. The eastern Riverside County desert communities (Palm Springs, Coachella Valley) fall under CEC Climate Zone 15 — a separate climate zone with even higher cooling design conditions.

Local Electric Utility: Riverside Public Utilities

Building Department: City of Riverside Building & Safety Division

Local Trade Association: ACCA California / ASHRAE Inland Empire Chapter