Bentonville

Warren County, Virginia regulates accessory dwelling units through its Zoning Ordinance, administered by the Department of Planning and Zoning (and the companion Department of Building Inspections) and adopted by the Warren County Board of Supervisors. Virginia is a Dillon Rule state and has NOT enacted a statewide ADU preemption law — Va. Code § 15.2-2280 et seq. delegates zoning authority entirely to localities — so every ADU rule that applies to a Warren County parcel is local. Warren County contains a single incorporated town, the Town of Front Royal (the county seat at the confluence of the North and South Forks of the Shenandoah River), plus five magisterial districts of unincorporated county (Fork, Happy Creek, North River, Shenandoah, and South River). Under Virginia's unusual city/town/county structure, incorporated towns in Virginia remain governed BY their counties for zoning in addition to their own town zoning when a town has adopted one — so for a parcel inside the Town of Front Royal's corporate limits, the Town of Front Royal's ordinance is the primary local rule set, while for an unincorporated parcel anywhere else in the county, the Warren County Zoning Ordinance is the operative rule set. The Warren County Zoning Ordinance permits accessory-dwelling uses (variously termed 'accessory apartments', 'family apartments', 'accessory dwelling units', or 'secondary dwellings' in different ordinance sections) subject to zoning-district conditions in certain districts; the county's Agricultural District (A), Residential (R-1) and related residential districts, and Rural Residential (RR) designations include specific provisions for single-family-dwelling-related accessory units, and an Agricultural-district 'family' dwelling provision historically allowed a second dwelling for a family member on larger parcels. Because Virginia's 2022-2025 General Assembly sessions did not enact statewide ADU preemption, accessory-dwelling approval in Warren County is a locally-administered process without a statewide ministerial-review floor, minimum ADU size, parking cap, or owner-occupancy preemption.

• Warren County Code — Zoning Ordinance (Accessory uses, family apartments, and accessory dwelling provisions)
• Warren County Code — Subdivision Ordinance and supplementary land-use regulations
• Warren County Comprehensive Plan — Land-use and housing elements
• Virginia Code § 15.2-2280 et seq. — State zoning enabling authority (Dillon Rule)
• Virginia Code § 15.2-2316.3 — Statutory safe harbor for family-member accessory dwelling

State-floor overlay: None. Virginia has not enacted a statewide ADU preemption law. Va. Code § 15.2-2280 et seq. delegates zoning authority to localities without imposing a floor on ADU permissibility, ministerial approval, minimum size, or parking. Warren County's Zoning Ordinance is therefore the operative rule set for every ADU question — allowance by district, size limits, owner-occupancy, parking, permit process, and fees are all locally set. ADU bills introduced in the 2022-2025 General Assembly sessions did not advance; the 2026 session had not closed the gap as of 2026-04-21. Additionally, note that the Town of Front Royal (the county's sole incorporated town, the county seat, and the location of roughly one-third of the county's population) maintains its own town zoning — for a town-limits parcel, the Town of Front Royal ordinance and any county supplemental rules apply; for an unincorporated county parcel outside the town limits, only the county ordinance applies.

Warren County, Virginia administers or cooperates in several overlay and environmental-review regimes that can affect ADU siting on unincorporated parcels: (1) FEMA Special Flood Hazard Areas along the county's principal watercourses — the North Fork and South Fork of the Shenandoah River (which converge at Riverton, in the Town of Front Royal's northeast quadrant, to form the main stem of the Shenandoah), Happy Creek, Crooked Run, Passage Creek (draining Fort Valley between Massanutten Mountain's Green Mountain and Three Top Mountain ridges, which passes through the extreme western margin of the county), and numerous tributaries — subject to the county's floodplain-management ordinance; (2) Shenandoah National Park / Blue Ridge corridor review — the park's northern entrance and the northern terminus of Skyline Drive sit at Front Royal, and the park's western boundary runs the length of the county's eastern edge along the Blue Ridge, creating a distinctive federal-land interface for Happy Creek district and South River district parcels; (3) historic overlay / advisory review — Warren County has significant Civil War heritage (the 1862 Front Royal battle during Stonewall Jackson's Valley Campaign, and the 1864 Cedar Creek area partially extending from Frederick / Shenandoah into Warren), 18th- and 19th-century agricultural-settlement heritage, and numerous individual properties on the Virginia Landmarks Register and National Register of Historic Places including Front Royal historic resources; (4) karst / sinkhole geology review — portions of the county's valley-floor geology include carbonate bedrock with sinkholes, closed depressions, and compromised septic-drainfield suitability, although the county's eastern quadrant is on Blue Ridge metamorphic geology rather than valley carbonate; (5) George Washington National Forest interface — portions of the county's western margin (Massanutten Mountain / Fort Valley) abut the Lee Ranger District of the George Washington National Forest, creating significant forest / wildland interface; (6) Chesapeake Bay Preservation Act — Warren County lies in the Potomac River drainage (Shenandoah River → Potomac at Harpers Ferry) and within the statewide Tidewater/non-Tidewater reach of the Act's erosion-and-sediment-control and stormwater-management provisions. Unlike California, Virginia does not maintain a Very-High-Fire-Hazard Severity Zone regime triggering mandatory WUI-rated construction.

• FEMA Special Flood Hazard Areas / Warren County Floodplain Management Ordinance — Warren County's floodplain-district regulations enforce FEMA NFIP minimum floodplain-management standards. Applicants should confirm effective FIRM panel numbers and BFEs at design time. The North Fork and South Fork Shenandoah and main-stem Shenandoah River have well-mapped floodplain; parcels close to any of these, or to secondary drainages like Happy Creek, are the most likely to face floodplain-district constraints. FEMA is conducting ongoing FIRM updates in the Potomac drainage basin, and effective panels should be verified before design commitments.
• Shenandoah National Park / Blue Ridge corridor federal-land interface — The park and the Appalachian Trail do not impose private-parcel zoning directly, but the park boundary has practical implications for accessory-dwelling siting: Park-facing viewshed concerns may appear in ridgeline-parcel special-use-permit reviews; access-road standards for remote upper-slope parcels can be rate-limiting; and wildfire-interface considerations (while Virginia has no formal VHFHSZ regime analogous to California) are amplified on park-adjacent parcels. Applicants with park-adjacent parcels should expect longer pre-application consultation timelines with Planning and Zoning than applicants on valley-floor parcels.
• Warren County historic-preservation review / Historic overlay and advisory review — Historic-overlay review does not typically prohibit an accessory dwelling outright but may add design-review requirements (materials, scale, siting, fenestration) for construction on or adjacent to designated historic resources. National Register listing alone is honorary and does not by itself impose design review; local historic-district overlay adoption under Va. Code § 15.2-2306 is what creates binding local design review. Applicants with historically-significant parcels should consult Planning and Zoning early to determine whether their parcel is subject to an overlay or only to advisory review.
• Karst / sinkhole geotechnical review (valley-floor carbonate bedrock) — Karst review is not a formal 'overlay' in the zoning-ordinance sense — it is a set of engineering and health-department constraints applied parcel-by-parcel. An accessory dwelling that requires a new or expanded septic drainfield on a karst-affected parcel is the category most likely to face substantive review, including geotechnical investigation, hydrogeologic evaluation, and alternative septic-system design (sand-mound, drip-irrigation, or advanced treatment systems approved by VDH). Groundwater-protection considerations are heightened because karst systems can transmit contamination rapidly from surface infiltration to private wells downgradient.
• George Washington National Forest interface and Massanutten Mountain ridge (forest / wildland interface) — There is no Warren County-specific WUI ordinance comparable to western-state WUI regimes. Construction standards for accessory dwellings on forest-interface parcels follow the general Virginia USBC; voluntary Firewise USA measures (defensible space, ignition-resistant materials, roof and vent design, Class-A roof assemblies) are encouraged but not mandated by county zoning. Access for wildland firefighting apparatus on steep or long-driveway parcels can be a practical permitting consideration that Planning and Zoning or Building Inspections may flag during site-plan review — especially on ridgeline and upper-slope parcels along either the Blue Ridge or Massanutten margins.
• Virginia Chesapeake Bay Preservation Act / stormwater and erosion-and-sediment-control requirements — The ESC / stormwater requirements are land-disturbance-based, not ADU-specific. Their relevance to an accessory-dwelling project depends on the site-disturbance footprint rather than the dwelling program. Applicants should request a pre-application conference with Planning and Zoning if the parcel involves steep slopes, proximity to streams, or significant site grading — situations common on Blue Ridge and Massanutten slopes and on river-frontage parcels in this county.

Warren County, Virginia's Department of Planning and Zoning (zoning, site-plan review, subdivision, and land-use approvals) and the county's Department of Building Inspections (building-permit, plan review, and inspection services under the Virginia Uniform Statewide Building Code) jointly administer ADU / accessory-dwelling permitting for parcels in the unincorporated county. Warren County contains a single incorporated town — the Town of Front Royal (the county seat) — which under Virginia law remains inside the county's jurisdiction; Front Royal has its own town zoning and its own Town of Front Royal building-permit administration, but the county retains jurisdiction over unincorporated parcels (the vast majority of the county's approximately 216 square miles, including all parcels in the Fork, Happy Creek, North River, Shenandoah, and South River magisterial districts outside town corporate limits). Warren County's permitting path for an accessory dwelling on an unincorporated parcel is sequenced: (a) zoning determination by Planning and Zoning confirming the parcel's district and the district's accessory-dwelling allowance; (b) special-use-permit or conditional-use-permit application heard by the Planning Commission and decided by the Board of Supervisors when required by the zoning district; (c) building-permit application to county Building Inspections; (d) Lord Fairfax Health District (Virginia Department of Health) approval for on-site septic and private-well where applicable (the majority of Warren County's rural parcels outside Front Royal are on private well and septic, not public water/sewer); (e) inspection and certificate of occupancy.