Backyard project permits in Fairfax County, VA
Fairfax follows Virginia's statewide exemptions (sheds up to 256 sq ft, fences of any height), but zoning still decides where a shed can sit and caps front-yard fences at 4 ft.
Rules last checked by a person on October 20, 2026. Guidance only; confirm with Fairfax County before you build.
| Typical project | Permit? |
|---|---|
| Shed10 by 12 ft shed, 10 ft tall, no power | No: no permit as described |
| Deck160 sq ft freestanding deck, 24 in high | Yes: Building permit |
| Fence6 ft wood fence in the back yard | Probably not: no permit as described |
| Garage24 by 20 ft detached garage with lights | Yes: Building permit, Electrical permit |
| ADU650 sq ft detached backyard cottage | Yes: Building permit, ALU administrative permit (interior) or BZA special permit (detached) |
Check your exact lot
Permit office
Virginia USBC (2021) and the Fairfax County Zoning Ordinance (zMOD, as amended through May 6, 2026).