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

4 of the zoning code governs accessory structures other than accessory dwelling units, garages, carports, fences, ground-mounted solar, flagpoles, playground equipment without a footer, and sheds that do not require a footer and are not permanently affixed to the ground; those specific items sit outside this section's reach. For everything else, subsection (B) bars accessory structures from the front yard on residential lots, though non-residential uses may place them there. The setback scales with size: a structure of 200 square feet or less must sit at least 2 feet from any lot line, while anything larger than 200 square feet must sit at least 10 feet from any lot line unless the planning commission approves otherwise.

Every accessory structure must also fit within the maximum building and impervious lot coverage limits of its zoning district, and unless the planning commission approves a larger footprint, no accessory structure may exceed 800 square feet or stand taller than 15 feet. A homeowner building a small, unfooted shed avoids the building-permit trigger altogether: the residential code amendment at section 5-5(6) exempts 'one story detached accessory structures less than 200 square feet in area including, but not limited to, storage sheds, kiosks, gazebos, arbors, or playhouses' from needing a permit at all, meaning the 2-foot and 10-foot zoning setbacks still apply even when no permit is required.

Garages and carports fall under a separate set of standards in subsection (C): a 2-foot side/rear setback, a 576-square-foot footprint cap, and the same 15-foot height limit, unless the planning commission approves more.