ADU Rules in Leesburg, Virginia

Leesburg is the county seat of Loudoun County and a town — meaning it is NOT one of Virginia's 38 independent cities. As a town, Leesburg is part of Loudoun County but has its own town government (mayor and town council) and its own zoning authority. Properties within Leesburg's town limits are governed by Town of Leesburg regulations; properties in Loudoun County outside the town limits use Loudoun County's separate zoning rules. This distinction is important because the two systems are different.

Leesburg has approximately 56,000 residents and has been one of the fastest-growing communities in Virginia. The town sits in the Dulles Airport corridor on the western edge of the Northern Virginia metropolitan area, with the Dulles Greenway (Route 267) connecting it to Dulles Airport and the DC Beltway. Leesburg has a nationally recognized historic downtown centered on King Street and the old courthouse, with architecture dating to the colonial and Federal periods. The town balances strong growth pressure with preservation of its historic character.

Virginia statewide ADU law status

Virginia has no enacted statewide ADU preemption: SB 304 (2024) would have required by-right ADUs, but was deferred to the Virginia Housing Commission and not enacted. Va. Code § 15.2-2292.1 covers only temporary family health-care structures. Given the rapid growth and high housing costs in the Dulles corridor, ADUs represent a meaningful additional housing option for Leesburg homeowners.

Leesburg Local Zoning for ADUs

The Town of Leesburg's zoning ordinance includes single-family residential districts. Typical ADU standards include:

• Maximum size: Generally limited to 1,200 square feet or a percentage of the primary dwelling's floor area
• Unit count: One ADU per single-family lot
• Types: Detached (new rear-yard structure), attached (addition to primary dwelling), or internal (basement, garage, or attic conversion)
• Setbacks: Detached ADUs must meet applicable rear and side setbacks; Leesburg's older sections have smaller lots while newer suburban sections have larger lots
• Height: Detached ADUs are typically limited to one story or approximately 16 feet
• Lot coverage: Combined structures must not exceed the district maximum
• Utilities: Town water and sewer connection required for properties served by the system

Contact the Leesburg Planning and Zoning Department at (703) 771-2765 or visit leesburgva.gov/government/departments/planning-zoning for the current ordinance language and any adopted ADU provisions.

Historic Downtown and H-1/H-2 Overlays

Leesburg's historic downtown and adjacent residential neighborhoods are among the best-preserved colonial and antebellum communities in Northern Virginia. The town has historic overlay districts — typically designated H-1 (Old Town Historic District) and similar designations — governed by the Board of Architectural Review (BAR):

• Properties in the H-1 overlay require BAR approval for all exterior changes, including adding any visible new structure
• Detached ADUs in the rear yards of H-1 properties will need BAR review for compatibility in scale, massing, and materials
• Interior ADUs (basement conversions, above-garage conversions with no exterior change) generally do not require BAR review
• BAR review adds time; schedule a pre-application consultation with BAR staff before designing

The historic overlay applies to a defined geographic area centered on downtown; suburban residential neighborhoods farther from the historic core are generally not in the H-1 overlay. Verify your specific property's overlay status with the Planning Department.

Dulles Airport — Noise and AICUZ Context

Washington Dulles International Airport is approximately 10 miles east of downtown Leesburg in the Dulles corridor area. Dulles is a large international airport served by Dulles Access Road and Route 28. Most Leesburg neighborhoods are sufficiently far from the airport that Dulles AICUZ noise contours (65 dB DNL or above) do not reach into the town. However:

• Properties on the eastern edge of Leesburg (near Route 28 or the Kincaid Forest/Lansdowne corridors approaching Dulles) may be closer to airport noise contours
• The Silver Line Metro extension to Dulles has been completed, with stations in Loudoun County; this may affect transit-related parking requirements for future ADUs near Loudoun County Metro stations (though most Leesburg properties are not within walking distance of the stations)
• Verify with the Planning Department whether any Dulles AICUZ overlay applies to your specific parcel

Loudoun County Context

Because Leesburg is a town within Loudoun County, certain county-level reviews or services may interact with town permits:

• Loudoun County Water and Sanitation may be involved in utility connections, depending on the area
• State and county environmental regulations (stormwater, Chesapeake Bay, wetlands) apply regardless of town vs. county jurisdiction
• If your property was previously in the county and was recently annexed into the town, zoning history may be complex

Permitting Process

1. Confirm you're in the Town of Leesburg (not Loudoun County unincorporated) — Call (703) 771-2765
2. Determine zoning district and historic overlay — Check GIS or contact Planning
3. Pre-application consultation — Leesburg Planning and Zoning, (703) 771-2765
4. BAR pre-application (if in H-1 or other historic overlay) — Contact early
5. Building permit application — Submit to the Department of Planning and Zoning / Building Official
6. BAR hearing (if required) — Coordinate with building permit timeline
7. Inspections and Certificate of Occupancy — Required before occupancy

Contact Information

• Town of Leesburg Planning and Zoning: (703) 771-2765 | leesburgva.gov/government/departments/planning-zoning
• Building Official: (703) 771-2765
• Municipal Code: library.municode.com/va/leesburg/codes/code_of_ordinances

Disclaimer: This guide provides general information only and is not legal or planning advice. Zoning regulations, historic overlay boundaries, and Dulles Airport AICUZ contours change over time. Always verify current requirements directly with the Town of Leesburg Planning and Zoning Department and the official municipal code before making any development decisions.