Accessory Structures in Orange County, CA (2026)

5 county-level rules, plus city-specific rules for 10 cities in Orange County, California.

Verified from official government sources

Note: These county rules apply to unincorporated areas of Orange County. If you live within an incorporated city, that city's own rules apply — see the city list below.

ADU Rules

In unincorporated Orange County, Zoning Code Sec. 7-9-90 allows one ADU plus one JADU on single-family lots through a ministerial permit, consistent with California ADU law. Detached or attached ADUs may reach 1,200 sq ft; JADUs up to 500 sq ft.

Orange County Accessory Dwelling Unit (ADU) Rules

Few Restrictions

Full ordinance details →Official source ↗

Shed Rules

Unincorporated Orange County Zoning Code Sec. 7-9-116 exempts one small detached non-habitable structure under 120 sq ft and 8 feet tall per 7,200 sq ft of lot from setback/coverage rules, if kept 3 feet from rear/side lines and 6 feet from other buildings.

Orange County Shed and Accessory Structure Rules

Some Restrictions

Full ordinance details →Official source ↗

Garage Conversions

In unincorporated Orange County, an existing garage or carport may be converted to an ADU under Zoning Code Sec. 7-9-90, and no replacement parking is required when a garage is converted to or removed for an ADU, consistent with California state law.

Orange County Garage Conversion Rules

Few Restrictions

Full ordinance details →Official source ↗

Carport Rules

A carport in unincorporated Orange County is an accessory structure under Zoning Code Sec. 7-9-116. Unenclosed carports may cover up to 50% of a side or rear required setback area, and an existing carport may be removed for an ADU without replacing parking.

Orange County Carport Rules

Some Restrictions

Full ordinance details →Official source ↗

Tiny Homes

Unincorporated Orange County has no dedicated movable-tiny-home ordinance. A permanent, foundation-built tiny home can qualify as an ADU under Zoning Code Sec. 7-9-90 (up to 1,200 sq ft). Tiny homes on wheels are generally treated as RVs under California HCD rules.