Richmond

Hanover County regulates accessory dwellings under its Chapter 26 Zoning Ordinance. As of 2026-04-21, Hanover has NOT enacted a modern ADU-preemption-style ordinance permitting detached accessory dwelling units ministerially on single-family-residential parcels. The county's framework permits accessory 'family member' dwellings and certain accessory apartments under narrow conditions — most commonly in agricultural (A-1, AR-1, AR-2, AR-6) zones, and through conditional-use permit (CUP) or special-exception review in residential (R-1, R-2, RC, RS, RR) districts — with owner-occupancy, family-relationship, size, and minimum-lot-area conditions typical of pre-preemption Virginia county ordinances. Because Virginia is a Dillon Rule state with no statewide ADU preemption (see src/data/state-adu-research/virginia.json for the statewide framework), Hanover's Chapter 26 is effectively the sole floor: where the ordinance does not explicitly allow a second dwelling, it is prohibited. Applicants planning an accessory dwelling in unincorporated Hanover should (a) confirm the parcel's zoning classification on the county's GIS viewer, (b) consult Chapter 26 Article (Districts and District Regulations) for the governing use table for the parcel's district, (c) verify whether the proposed accessory-dwelling use fits a permitted, conditionally-permitted, or prohibited category, (d) engage Planning Department staff in a pre-application conference, and (e) budget for a conditional-use-permit or special-exception public-hearing process where Chapter 26 requires it. The Town of Ashland's rules (a separate ordinance) control for any parcel inside the Ashland town limits. Hanover is one of the faster-suburbanizing Central Virginia counties, particularly in the Mechanicsville / Atlee area and along the US-1 / I-95 corridor through Doswell, and the Board of Supervisors has periodically considered ADU-adjacent policy questions as part of comprehensive-plan updates (Envision Hanover) without yet enacting broad by-right ADU allowances.

• Code of the County of Hanover, Chapter 26 (Zoning Ordinance) — Article (General Provisions), Article (Definitions), Article (Districts and District Regulations), Article (Supplementary Use Regulations and Accessory Uses)
• Virginia Code § 15.2-2280 et seq. (zoning enabling authority for Virginia counties, cities, and towns); § 15.2-2286 (provisions that may be included in a zoning ordinance); § 15.2-2285 (procedure for amending a zoning ordinance); § 15.2-2230 (comprehensive plan five-year update requirement); Dillon Rule doctrine
• Envision Hanover (Hanover Comprehensive Plan) — the advisory document that guides Chapter 26 amendments on the Va. Code § 15.2-2230 five-year review cycle
• Hanover County Charter and Code of the County of Hanover generally (non-zoning chapters) at library.municode.com/va/hanover_county

State-floor overlay: Virginia has NOT enacted a statewide ADU preemption law. Va. Code § 15.2-2280 et seq. delegates zoning authority to counties, independent cities, and towns, subject to planning-commission procedure and advertised public hearing. No state floor mandates ADU permissibility, ministerial review, minimum allowed size, parking-requirement ceilings, or removal of owner-occupancy requirements. Localities can and do prohibit ADUs entirely under this framework, subject only to federal equal-protection / fair-housing limits and the state's general-welfare zoning-purpose constraints. ADU preemption bills have been introduced in the 2022, 2023, 2024, and 2025 Virginia General Assembly sessions without enactment; none passed both chambers. Hanover County's Chapter 26 therefore operates without a state ceiling on local restrictions — whatever Chapter 26 says controls, subject to the usual state-law procedural requirements on amendment (advertised hearings, Planning Commission recommendation, Board vote). See src/data/state-adu-research/virginia.json for the full statutory framework.

• wetland-overlay — Applicants should always pull a parcel's RPA / RMA overlay on the county GIS viewer before siting any detached accessory dwelling; a structure inside the RPA buffer will trigger administrative-review requirements at minimum, and frequently leads to relocation of the proposed building envelope outside the buffer as the cheapest compliance path. The Virginia Department of Environmental Quality (DEQ) provides statewide CBPA guidance at deq.virginia.gov/our-programs/water/chesapeake-bay. Hanover's CBPA program has been in place since the original statewide CBPA designation of Tidewater localities and has evolved through periodic Chapter 26 and companion-chapter amendments.
• flood-zone — FIRM maps published by FEMA are the authoritative flood-zone source; the county's GIS viewer overlays current effective FIRMs on the parcel layer. Finished-floor elevation requirements for residential construction in SFHAs typically require the lowest floor (including basement) to be at or above the base-flood elevation (BFE), with Hanover commonly imposing freeboard above BFE per its local ordinance consistent with NFIP minimum standards. Flood-zone status also affects flood-insurance cost under NFIP Risk Rating 2.0 (the 2021-2023 methodology reset). Rural Hanover's large-lot parcels frequently have a portion of the parcel in SFHA along a creek and a larger portion out of SFHA, making building-envelope siting the critical design question rather than whether the parcel is developable at all.
• airport-noise-zone — Applicants building an accessory dwelling near KOFP should check parcel status against any airport-overlay layer on the county GIS viewer. Height restrictions are the most common constraint for parcels within transitional surfaces; residential-use compatibility and a real-estate disclosure obligation may apply within designated noise contours. The county does not prohibit residential use within the airport overlay but does apply height limits and process additional notifications. Note: Hanover County Municipal Airport is a general-aviation field, not an air-carrier airport — the noise contours and FAA review footprint are meaningfully smaller than at a commercial-service airport like KRIC.
• historic-district — Register-listed (National or Virginia) status alone does NOT by itself create a local review requirement; only locally-designated historic-overlay district status does. However, federal preservation tax incentives (26 U.S.C. § 47 Historic Rehabilitation Tax Credit) and Virginia state rehabilitation tax credits (Va. Code § 58.1-339.2) do apply to register-listed properties and can materially improve the economics of an ADU-adjacent rehab if the property qualifies. The Virginia Department of Historic Resources (dhr.virginia.gov) administers the state registers and reviews state-tax-credit rehabilitation applications. Hanover-Caroline Historical Society and the Hanover Historical Society (affiliated with the Scotchtown property) are the primary non-governmental historical-resources organizations in the county.
• other — Applicants contemplating an ADU on a rural Hanover parcel should (a) pull the parcel's prior VDH septic-construction-permit file from the Chickahominy Health District (records are maintained for decades in most cases), (b) assess whether the existing drainfield has reserve capacity for the additional dwelling's load (VDH has per-bedroom loading standards), (c) obtain a soil-evaluation letter from a licensed Onsite Soil Evaluator if the existing permit file is incomplete or the drainfield is close to capacity, and (d) budget $15,000-$45,000 or more for drainfield expansion / replacement on typical Hanover soils, with higher costs in areas of poor percolation. This is a crucial no-surprises step because a rural Hanover ADU can be fully permitted by Chapter 26 and Building Inspections and still fail at VDH review on wastewater-capacity grounds.

Every parcel in Hanover County outside the Town of Ashland is unincorporated (Hanover contains no independent cities and only one incorporated town — Ashland — so the unincorporated area is the dominant geography). The Hanover County Department of Community Development (which houses Planning, Zoning, Building Inspections, and Environmental Services) is the principal permitting authority for any accessory-dwelling construction in unincorporated Hanover. The combined permit path is a two-track review: (a) a zoning-compliance determination confirming the proposed accessory dwelling fits a permitted or conditionally-permitted category under Chapter 26 (handled by the Planning / Zoning staff), and (b) a building-code plan review and inspection cycle confirming compliance with the Virginia Uniform Statewide Building Code (USBC), which incorporates the Virginia Residential Code and associated state-adopted supplements (handled by Building Inspections). For parcels where Chapter 26 does not permit a second dwelling by right, the applicant must first obtain a conditional-use permit (CUP), a special exception, or a zoning variance (the specific mechanism depends on the Chapter 26 category governing the intended use), processed through the Planning Commission and Board of Supervisors per Va. Code § 15.2-2285 or through the Hanover County Board of Zoning Appeals where the Chapter 26 text routes the matter there. Hanover uses online permit portals and customer-service counters at the Hanover County Government Complex in Hanover (courthouse area) for building-permit intake, and offers free pre-application conferences with Planning staff for zoning questions.