Every newly constructed detached ADU in Los Angeles County, California must include a Title 24-compliant solar PV system. Los Angeles County spans climate zones 6, 8, 9, 14, 16, which determines exactly how many kilowatts your specific project must install for code compliance.
Local building departments across Los Angeles 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 most populous county in the U.S., Los Angeles County has massive ADU development driven by housing demand. LA's ADU ordinance is among the most permissive in California, making solar-equipped ADUs a top investment strategy.
Title 24 multiplies your ADU's conditioned floor area by a climate-zone-specific kW factor. Across Los Angeles County's climate zones 6, 8, 9, 14, 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 Los Angeles County. HDM financing typically reduces effective cost by ~40% via commercial ITC pass-through. Main utilities serving the county: LADWP, SCE, PG&E.
Yes. Title 24 is California state law and every jurisdiction in Los Angeles County enforces it at permit submittal.
Los Angeles County sits in climate zones 6, 8, 9, 14, 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.