Westminster, CA Accessory Structures: Shed Rules (2026)

Detached residential accessory structures in Westminster are governed by Municipal Code Section 17.400.130 (Residential Uses—Accessory Structures), part of the city's Zoning Code (Title 17). Per the codified text, a detached accessory building or structure of 120 square feet or less and 7 feet or less in height—including children's playhouses—is exempt from the zoning development restrictions (but not the Building and Fire codes), provided it sits behind a line extending from the exterior wall of the main dwelling nearest the street, no closer than the minimum setback line, and no part crosses a property line. Larger detached structures must observe a 3-foot setback from interior side and rear property lines when located in the rear one-third of the lot; structures in the front two-thirds must meet the main-building setbacks. A 10-foot street-side setback applies on corner lots. Maximum structure height is generally 15 feet to the roof peak. Accessory structures may not be used as habitable space—the city's code enforcement guidance states that sheds, workshops, garages, and enclosed patios are not designed for habitation and that living in accessory structures is prohibited (a habitable second unit must instead qualify as an ADU). These are city-specific zoning standards; Orange County standards do not apply inside the incorporated city.