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

Under Zoning Regulations Section 128.0, the required setbacks from side or rear lot lines for accessory structures on lots improved by single-family detached dwellings are: detached accessory garages or sheds, zero feet; other accessory structures, five feet from the side and ten feet from the rear. A freestanding carport falls under these accessory-structure standards and counts toward the cumulative lot-coverage cap for the lot's zoning district. Because accessory structures may not contain living space, a carport cannot be enclosed into habitable rooms without meeting accessory-apartment rules. Structures attached to the dwelling and building additions are instead subject to the principal-dwelling setbacks in Title 3, Subtitle 1 of the Howard County Building Code.