Accessory Structures in Antioch, CA (2026)
5 verified accessory structures rules for Antioch, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
California state law (AB 68, SB 13, AB 881, and subsequent legislation) broadly permits ADUs in all single-family zones. Antioch must comply with state ADU law, allowing both attached and detached ADUs with streamlined permits.
Antioch ADU (Accessory Dwelling Unit) Rules
Some RestrictionsShed Rules
Sheds in Antioch must comply with setback and size requirements. Sheds under 120 square feet and single story may be exempt from building permits but must meet zoning placement rules.
Antioch Shed & Outbuilding Rules
Some RestrictionsGarage Conversions
Garage conversions in Antioch may be facilitated by California ADU law, which allows converting existing garages into ADUs or junior ADUs without replacing the parking spaces.
Antioch Garage Conversion Rules
Some RestrictionsCarport Rules
Carports in Antioch are governed by the Zoning Code as accessory structures. Detached carports must sit behind the front yard setback, must be at least 5 feet from interior side and rear lot lines (20 feet from a side street on a corner lot), and may not exceed 15 feet in height. The garage or carport opening serving a residence must be at least 20 feet from the exterior property line so a parked car will not overhang the sidewalk.
accessory-structures/carport-rules
Some RestrictionsTiny Homes
Antioch regulates tiny homes through its ADU ordinance at Antioch Municipal Code 9-5.3805, which expressly recognizes manufactured homes (Cal. Health & Safety Code 18007) and efficiency units (Cal. Health & Safety Code 17958.1) as Accessory Dwelling Units. A detached tiny-home ADU is permitted up to 1,200 square feet at 16 feet in height with 4-foot side and rear setbacks. Tiny homes on wheels (THOWs), park-model RVs, and recreational vehicles are not recognized as ADUs and may not be used as permanent dwellings outside a permitted park.
accessory-structures/tiny-homes
Some RestrictionsLooking for Contra Costa County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Antioch city rules.
Accessory Structures in Contra Costa County →