Macon County, IL Accessory Structures: Shed & Carport Rules (2026)

051(B) sets the bulk standards for accessory buildings, sheds, detached garages, and similar structures on residentially and agriculturally zoned property in the unincorporated county. 183 table, or the block's average setback, capped at 50% more than the district minimum. 183, though a shed that is not used as a residence or for livestock storage and sits at least 60 feet back from the front property line gets a reduced three-foot side and rear setback. Corner lots require a street-side setback equal to the front-yard minimum.

An accessory building cannot cover more than 30% of the required rear yard or 50% of a required side yard, and it must sit at least ten feet from the principal building unless it is built to full principal-building construction standards and attached. Height is capped at 25 feet, measured from the top of the lower floor to the roof peak, for residential accessory buildings, including those on tracts under ten acres zoned A1 Agricultural. 051(B)(9)(a) requires a building permit for any accessory building longer than ten feet on any side, and no permit for an accessory building can issue before the principal building it serves is under construction. Stables, barns, and buildings housing animals or livestock carry a separate 75-foot setback from all property lines under (B)(1).