Every newly constructed detached ADU in Santa Clara County, California must include a Title 24-compliant solar PV system. Santa Clara County spans climate zone 4, which determines exactly how many kilowatts your specific project must install for code compliance.
Local building departments across Santa Clara 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.
Santa Clara County, home to Silicon Valley, has some of the highest property values in the nation. ADU construction is booming as homeowners add rental units. San Jose Clean Energy and Silicon Valley Power offer community choice energy options.
Title 24 multiplies your ADU's conditioned floor area by a climate-zone-specific kW factor. Across Santa Clara County's climate zone 4, 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 Santa Clara County. HDM financing typically reduces effective cost by ~40% via commercial ITC pass-through. Main utilities serving the county: PG&E, SJCE, SVP.
Yes. Title 24 is California state law and every jurisdiction in Santa Clara County enforces it at permit submittal.
Santa Clara County sits in climate zone 4. 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.