Tonawanda, NY Accessory Structures: Shed & Carport Rules (2026)

Section 54-5.B(1) exempts one-story detached tool and storage sheds, playhouses and similar structures serving a one- or two-family dwelling or townhouse from the building permit requirement, but only while the gross floor area stays at or under 144 square feet. Anything larger needs a full building permit under § 54-5.A, examined by the Code Enforcement Officer within 60 days per § 54-5.I. Section 54-5.C is explicit that the size exemption never authorizes work that would otherwise violate the Uniform Code or Energy Code, so an oversized or unsafe shed built under the exemption is still a violation.

Separately, the zoning code caps how many accessory structures a lot may carry at all: § 215-24.4.A(4) limits any lot to one attached and/or detached garage plus up to two additional sheds or other fully enclosed accessory structures, and if both an attached and detached garage sit on the same lot their combined floor area cannot exceed 900 square feet. Section 215-24.4.A also requires every accessory structure, sheds included, to stay clearly incidental and subordinate to the primary structure, to be finished with materials compatible with the primary structure and neighborhood under Subsection A(5), and to avoid the required front yard under Subsection A(2).

Overhead electric circuits to a shed are barred; feeders must run underground under Subsection A(7). A permit application for a shed that needs one follows the same § 54-5.F requirements as any other building permit, including a site plan showing lot lines and distances to other structures.