Do I need a permit? across the DC area
Which small projects need no permit? The rules differ at every jurisdiction line. Here is the short answer for each.
Disclaimer: This is general information, not legal or professional advice for any one property. Codes change. SetbackIQ is not a zoning determination, a permit, or a survey, and it does not replace an architect, engineer, or lawyer. Confirm with your building and zoning offices before you build, buy, or sign a contract.
| Where | Short answer |
|---|---|
| Washington, DC | DC exempts very little: a single garden shed of 50 sq ft or less, playground equipment, a small prefabricated pool, a retaining wall up to 4 ft that disturbs under 50 sq ft, and like-for-like repairs. In a historic district even those need a permit. |
| Montgomery County, MD | Montgomery County permits every shed and every new fence. No permit is needed for patios, walkways, driveways on the lot, play equipment and treehouses, prefabricated pools under 18 in deep, or retaining walls up to 48 in with no surcharge. |
| Prince George's County, MD | DPIE exempts only four things: one detached accessory structure under 150 sq ft per lot, paving under 500 sq ft that isn't for parking, retaining walls 2 ft or less that support nothing, and fences 4 ft or less. |
| Alexandria, VA | Virginia's statewide code sets the building-permit exemptions, but Alexandria's zoning is tight: a shed in a required yard is limited to 100 sq ft (65 sq ft in historic districts), and the city's soil policy asks for a permit on retaining walls from 2 ft. In Old Town and Parker-Gray, the BAR reviews most visible exterior work. |
| Arlington County, VA | Arlington follows Virginia's statewide exemptions: sheds to 256 sq ft, fences of any height except pool barriers, retaining walls holding back less than 3 ft, small shallow pools and like-for-like electric HVAC swaps. Every deck needs a permit, and in an RPA even exempt work needs county review. |
| Fairfax County, VA | Virginia's statewide code sets Fairfax's building-permit exemptions: sheds up to 256 sq ft, fences of any height (except pool barriers), masonry walls up to 6 ft, retaining walls holding back less than 3 ft, small shallow pools and like-for-like electric HVAC swaps. Every deck needs a permit. Zoning and grading rules still apply. |
Towns and cities inside these counties (for example, Rockville, Gaithersburg, Bowie, Laurel, Herndon, Vienna, and Falls Church) have their own rules.