ADU rules in Loudoun County, VA — also called accessory dwelling unit regulations or granny flat ordinances — cover setbacks, owner-occupancy, parking, and permit requirements.
Loudoun allows accessory dwelling units in specific zoning districts under VA Code §15.2-2292.1. 2023 state law requires localities over 3,500 population to permit at least one ADU type.
Accessory dwelling units in Loudoun County are permitted in certain zoning districts under the Zoning Ordinance and Virginia Code §15.2-2292.1 (HB 2190, 2023), which requires localities with populations over 3,500 to allow at least one type of ADU. Loudoun's approximately 430,000 population makes this mandatory. Typical ADU conditions: maximum 600-800 sq ft or 35% of primary dwelling size, must comply with minimum lot size and setbacks, meet Virginia USBC for habitable dwellings, and connect to utilities. State law prohibits owner-occupancy requirements for attached ADUs and additional parking requirements beyond what applies to the primary dwelling. Detached ADUs (cottages, converted carriage houses) have additional scrutiny in western Loudoun historic and rural districts.
Unpermitted ADU construction: $500-$2,000 plus required retroactive permitting or demolition. Zoning violation: $250/day. USBC violations addressed via Building & Development.
Loudoun County, VA
Loudoun County has no leaf-blower-specific restrictions; use falls under general noise ordinance timing limits. Many Ashburn, Brambleton, and Leesburg HOAs s...
Loudoun County, VA
Loudoun driveways must meet VDOT entrance standards on state roads and county subdivision standards elsewhere. No parking on front lawns; driveway expansion ...
Loudoun County, VA
Loudoun Zoning Ordinance prohibits commercial vehicles over 12,000 lbs GVWR in residential zones. One work van typically allowed. Dulles-area trucking and da...
Loudoun County, VA
Loudoun permits wood, vinyl, aluminum, and 3-board wood fencing in horse country. Barbed wire restricted to agricultural zones. Historic districts require tr...
Loudoun County, VA
Virginia has no shared fence cost statute — each Loudoun property owner maintains their own fence. VA §55.1-2821 partition fence law applies to agricultural ...
Loudoun County, VA
Loudoun County does not ban specific breeds. Virginia does not preempt local BSL but Loudoun uses a behavior-based dangerous dog framework under VA §3.2-6540.
See how Loudoun County's adu rules rules stack up against other locations.
Help us keep this page accurate. If you notice an error or outdated information, let us know.