Allegany County, MD Accessory Structures: Shed & Carport Rules (2026)

Section 360-129A governs where a residential accessory structure, including a shed, detached garage or similar building, can go on the lot: side or rear yards only, positioned per the dimensional standards in § 360-126. In the county's urban districts, no residential accessory structure may sit in the front yard at all, a stricter rule than applies in nonurban areas. The county also closes an obvious loophole: mobile homes, travel trailers, motor homes, motor vehicle bodies, cargo boxes or similar devices cannot be used as accessory storage structures, so a shed substitute made from a shipping container or an old camper does not qualify.

On dimensions, Table 2 of § 360-126 treats residential accessory structures as a distinct row: no minimum lot area or width applies, but the structure still needs an 8-foot side setback and an 8-foot rear setback, identical to the setbacks required for the principal single-family dwelling on the same lot, and it is capped at 30 feet in height, footnoted to note that the county's Building Code can impose additional height and area limitations on top of the zoning number. A nonresidential accessory structure, by contrast, needs a 30-foot side and rear setback and carries no fixed height cap.

Section 360-129B further allows nonresidential accessory structures to sit on the same lot as other approved nonresidential buildings, provided setback and size requirements are met, and it does not require fresh Board of Appeals approval where the parcel already carries an approved special exception.