Westminster, CO Accessory Structures: Shed & Carport Rules (2026)

Section 11-9-3(A)(2) exempts from the permit requirement "one-story detached accessory buildings or structures used as tool and storage sheds, playhouses, gazebos, pergolas, and similar uses, provided that the floor area does not exceed 120 square feet." The exemption applies only to the building permit itself; the same section warns that exemption from permitting "shall not be deemed to grant authorization for any work to be done in any manner in violation of this Code or any other laws or ordinances of the City," so a shed still has to sit on the property in compliance with zoning setbacks and any applicable homeowners association rules even without a permit.

Sheds over 120 square feet lose the exemption entirely and are treated like any other accessory structure under Section 11-9-3(A)(1): the owner must apply for a building permit, pay the fee set in the City's Building Permit Fee Schedule, and pass inspection before use. The same 120-square-foot threshold also determines whether electrical wiring run to the shed needs its own permit review, since a wired shed is no longer limited to the narrow list of exempt electrical work such as portable equipment connections. Retaining walls built to support a shed pad over three feet in height likewise require a separate permit.