Every newly constructed detached ADU in San Bernardino County, California must include a Title 24-compliant solar PV system. San Bernardino County spans climate zones 10, 14, 15, 16, which determines exactly how many kilowatts your specific project must install for code compliance.
Local building departments across San Bernardino County enforce Title 24 at plan check. Plans submitted without a properly sized solar system are routinely rejected unless a documented exemption (shading, roof area, structural) applies.
The largest county by area in the contiguous U.S., San Bernardino County offers diverse ADU opportunities from suburban Inland Empire communities to mountain and desert towns. Solar production is excellent throughout the inland valleys.
Title 24 multiplies your ADU's conditioned floor area by a climate-zone-specific kW factor. Across San Bernardino County's climate zones 10, 14, 15, 16, most ADUs land in the 1.6–4.0 kW range — typically 4 to 10 modern (~400W) panels.
Title 24-compliant ADU solar packages range from $4,000 (Standard cash) to $15,000+ (Premium with battery) across San Bernardino County. HDM financing typically reduces effective cost by ~40% via commercial ITC pass-through. Main utilities serving the county: SCE, Bear Valley Electric.
Yes. Title 24 is California state law and every jurisdiction in San Bernardino County enforces it at permit submittal.
San Bernardino County sits in climate zones 10, 14, 15, 16. Use our cost calculator to map your exact ZIP code to its Title 24 climate zone.
Exemptions are project-specific, not countywide. The most common are shading (<70% annual solar access), insufficient roof area, and structural infeasibility. Your designer documents these on the CF1R compliance form.