Antioch, CA Accessory Structures: Shed & Carport Rules (2026)
Shed permit rules in Antioch, CA, also referred to as storage shed, backyard shed, or accessory building regulations, set size limits, setbacks, and when a building permit is required.
Key Facts
- Code section
- AMC § 9-5.603 (Accessory Buildings)
- Max height in residential
- 15 ft
- Interior side / rear setback
- 5 ft minimum
- Corner-lot side yard
- 20 ft minimum
- Double-frontage rear setback
- 10 ft
- Max rear-yard coverage
- 40% of required rear yard
- Min distance from any dwelling
- 5 ft (if unattached)
- Portable shed permit threshold
- <120 sq ft, <=8 ft tall, no foundation, no utilities
- Permit authority
- Building Services Division (925) 779-7065
Summary
Antioch Municipal Code Section 9-5.603 caps accessory structures in residential districts at 15 feet tall, requires a five-foot rear and interior side setback, and exempts truly portable storage sheds (under 120 sq ft, under 8 ft tall, no foundation) from permit requirements.
In residential districts, the maximum allowable height is 15 feet for accessory structures. Detached accessory structures shall be located behind the required front yard setback and cover no more than 40% of the rear yard area required for the main building. The minimum side yard for accessory structures is 20 feet on corner lots and five feet on interior lots. A five-foot rear yard setback is required, unless the property is a double-frontage lot in which case a ten foot rear yard setback is required.
Full Breakdown
603 ("Accessory Buildings") sets the zoning standards for detached sheds, gazebos, patio covers, and similar outbuildings in residential districts. The City defines accessory structures as buildings detached from the main building by more than five feet (sheds, gazebos, patio covers, and similar structures). In residential districts the maximum allowable height for an accessory structure is 15 feet, and detached accessory structures must be located behind the required front yard setback and cover no more than 40% of the rear yard area required for the main building.
The minimum side yard for accessory structures is 20 feet on corner lots and five feet on interior lots, with a five-foot rear yard setback (10 feet on double-frontage lots). When an accessory building is attached to the main building it is treated structurally as part of the main building and must meet all primary-dwelling standards; an unattached accessory building must sit at least five feet from any dwelling on the same lot or an adjacent lot. A portable storage shed is exempt from setback requirements when placed in the rear yard, but the required front and street-side setbacks still apply on corner lots.
A shed qualifies as portable - and is exempt from a building permit - when it is freestanding, moveable, and has no permanent foundation; is less than 120 square feet in area; is no more than 8 feet tall; and contains no plumbing or electrical installations. Larger or hard-wired sheds require a building permit through the Antioch Building Services Division and must comply with the currently adopted California Building Standards Code under Title 8 of the Antioch Municipal Code.
Violations & Fines
Sheds and accessory buildings that exceed the 120 sq ft / 8 ft / no-utility thresholds, or that violate the 5-foot rear setback or 15-foot height limit, can be cited under Antioch's code-enforcement process, requiring removal, relocation, or after-the-fact permitting. Construction of a permanent accessory building without a permit is also a violation of Title 8 (Building Code) and may trigger separate building-code citations and fees.
Frequently Asked Questions
Do I need a building permit for a shed in Antioch?
How close to the property line can my Antioch shed be?
How tall can a shed or accessory building be in Antioch?
Can my shed cover my whole back yard?
Sources & Official References
Other rules in Antioch
How Antioch compares: Shed Permit Requirements by City·California rules heatmap·Compare Antioch to another location·View the California accessory structures overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Shed & Carport Rules in Nearby Cities
How other cities in Contra Costa County handle shed & carport rules.