Ankeny, IA Accessory Structures: Shed & Carport Rules (2026)

Section 191.07 of the Ankeny Code of Ordinances governs accessory buildings, including sheds, garages, and detached workshops, on one-family and two-family residential lots. The building must go in the rear yard; the code allows no accessory building in any other yard except as specifically provided. Every accessory building, including garages, needs a minimum three-foot setback from the side and rear lot lines of adjoining lots. Garages that front an alley get a different rule: the general five-foot alley setback does not apply to them, and instead they must sit back either seven feet or a full 18 feet from the alley right-of-way.

Accessory structures on corner lots must meet the front yard setback on both streets under Section 191.05. On coverage, the code caps total accessory building area at ten percent of the lot's square footage, and no single accessory building for a one- or two-family lot can exceed 1,010 square feet. Every conforming one- and two-family lot is guaranteed the right to build up to 720 square feet of detached accessory space regardless of the ten-percent cap, so a smaller lot still gets a usable shed or garage allowance.

Height is capped too: an accessory building cannot exceed the height limit set for accessory buildings in its zoning district, and in residential districts it cannot rise above the height of a one-story principal building measured from grade to the roof peak. The Ankeny Planning and Building Department reviews accessory structure placement and size against these standards as part of any building permit review, and a shed built past the setback or size limits is out of compliance regardless of whether a permit was pulled.