Accessory Structures in Orange County, CA (2026)

4 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

Unincorporated Orange County allows ADUs on any residentially zoned lot under OC Zoning Code (Title 7, Division 9) and California Government Code §65852.2 (ADUs) and §65852.22 (JADUs). State law preempts most local restrictions: minimum 800 sqft, 16 ft height, and 4 ft side/rear setbacks must be allowed by right.

Orange County ADU & JADU Rules (Unincorporated)

Few Restrictions

Full ordinance details →Official source ↗

Shed Rules

Unincorporated Orange County exempts one small detached non-habitable accessory structure - a shed - per 7,200 square feet of building site area from accessory-structure standards under Section 7-9-116.1(h)(1) of the Codified Ordinances, provided it is under 120 square feet, no taller than 8 feet, set at least 3 feet from rear and side property lines, set at least 6 feet from another building, and not located in any front yard. Sheds beyond that allowance are accessory structures regulated by Section 7-9-116.1.

Orange County Shed Rules

Few Restrictions

Full ordinance details →Official source ↗

Garage Conversions

Unincorporated Orange County allows the conversion of an existing garage, carport, or accessory structure into an accessory dwelling unit (ADU) under Section 7-9-90 of the Codified Ordinances and California Government Code Section 65852.2. A garage-conversion ADU may be the size of the converted structure plus up to 150 square feet for ingress/egress, processed ministerially, and the parking space lost in the conversion does not need to be replaced.

Orange County Garage Conversions

Few Restrictions

Full ordinance details →Official source ↗

Carport Rules

Carports in unincorporated Orange County are governed by Section 7-9-70.3(d) of the Codified Ordinances, which requires carports to comply with main-building setbacks and provides specific rules for entry location, alley/driveway access, and placement in rear or interior side yards. Section 7-9-70.3(c)(2) requires 28 feet of unobstructed maneuvering area in front of a carport, and each covered space must be at least 10 feet by 20 feet under Section 7-9-70.3(a)(1). Building permits are required under Title 7 (adopted CBC).