ADU rules in Martinsburg

Martinsburg's Zoning Ordinance (Part Thirteen, Chapter Three of the Codified Ordinances, adopted as Ord. 2021-07 on 7-21-2021) lists Accessory Dwelling Unit as an accessory residential use in Table 1327-1: permitted by right in Urban Residential (UR), Downtown (DT) and Mixed Use Residential (MUR), by special exception from the Board of Zoning Appeals in Suburban Residential (SR), and not at all in Mixed Use Commercial (MUC) or Medical-Institutional (MIN). A detached unit must sit "in a detached accessory structure occupied, or formerly occupied, on the first floor by a garage, barn, or similar Accessory Use", so an apartment over a garage or a converted garage or barn qualifies but a purpose-built backyard cottage does not. The lot must be at least 7,500 sq ft and hold exactly one one-unit residential structure, and occupancy is tied to the owner's family (see the owner-occupancy and rental fields). From 1-1-2027 W. Va. Code §8-42-2 requires at least one attached, detached or internal ADU by right on every lot with a single-family dwelling, so the SR hearing, the garage-only form, the MUC and MIN exclusion and the lot minimum (where it exceeds the house's own minimum) become likely invalid under §8-42-3(c).

An attached or internal ADU may be placed "in a Principal Structure, provided that there is a separate entrance to the exterior or to an unconditioned porch type space", and that exterior entrance "shall not be visible from the front right of way". The same district split applies (by right with a Use and Occupancy Permit in UR, DT and MUR; special exception in SR; prohibited in MUC and MIN), as do the 7,500 sq ft minimum lot, owner occupancy and family-only occupancy, and no new separate utility connection may be installed for a unit inside the house unless the lot already has more than one. A different route for an internal second unit is converting the house to a Two-Family Dwelling (special exception in UR and SR, by right in DT and MUR, lots no larger than 10,000 sq ft), which carries no owner or family limits but needs two parking spaces per unit. From 1-1-2027 §8-42-2(a) and (b) require an attached or internal ADU by right on every single-family lot, and §8-42-2(d)(6) bars an ADU lot minimum stricter than the house's (UR-2 and SR-2 houses need 5,000 sq ft, UR-3 3,000, MUR 2,000).

§1327.08(b)(1)(E) caps the ADU's Usable Floor Area at 50 percent of the principal dwelling unit's Usable Floor Area or 1,000 sq ft, whichever is less; exterior patios, decks, porches and staircases giving interior access from the main unit are not counted. A detached unit is housed in an outbuilding governed by the transect building-form tables (1.5 stories in UR-2, SR-1 and SR-2; 2 stories in UR-3, DT-4 and MUR-3; 1 story in MUR-2; 3 in DT-5), and every accessory structure must stay at least 5 ft from alley, side and rear lot lines (§1329.01). W. Va. Code §8-42-2(c) caps attached and detached ADUs at 75 percent of the house's gross floor area or 1,000 sq ft, whichever is less, and sets no cap for internal units; with §8-42-2(d)(7) barring "more onerous development standards" beyond the article, the 50 percent figure is likely invalid from 1-1-2027 (and arguably any cap on internal units), while the 1,000 sq ft ceiling matches the statute.

§1327.08(b)(1)(B): "The property must be owner-occupied, either in the Principal Structure or principal Dwelling Unit, or in the Accessory Dwelling Unit and be related to at least one (1) adult occupying the Accessory Dwelling Unit" by blood, marriage, adoption, custodianship or guardianship. It is an ongoing condition rather than an application-day test: the unit is recognized through a Use and Occupancy Permit, a new U&O Permit is required on "any change in ownership" (§1321.09(a)(7)), and permits can be revoked for failure to comply (§1321.08(d)(10)); no deed restriction or recorded covenant is required. W. Va. Code §8-42 does not preempt owner occupancy (the clause that would have barred it was struck from SB 659 before passage), so the residency rule can survive 1-1-2027, but the attached relationship requirement cannot, because §8-42-2(d)(3) bars requiring "a familial, marital, or employment relationship" between the occupants of the house and the ADU. The text does not say how the relationship clause applies when the owner lives in the ADU.

§1327.08(b)(1)(F): "Parking for the Accessory Dwelling Unit must be provided on-site in accordance with the parking requirements specified in the Martinsburg Subdivision and Land Development Ordinance." That ordinance's Table 1307-4 (§1307.17(g), Ord. 2022-13) has no ADU row; its residential rows set 2.0 spaces per dwelling unit for single-family and two-family housing, the ratio staff applied in 2026 to a two-family conversion (BZA case 2025-110-SE, 530 Third Street: four spaces for two units). The table applies "in all districts except Downtown (DT)", the Planning Commission may accept an alternative parking program by waiver, and street parking can count for up to 10 percent of required spaces. From 1-1-2027 W. Va. Code §8-42-2(d)(1) bars requiring additional parking, or fees in lieu, for an ADU.

Table 1327-1 marks Accessory Dwelling Unit "R" (permitted by right) in UR, DT and MUR, where approval is a Use and Occupancy Permit reviewed and issued by the City Engineer/Planning Director (§1321.09; the current application form lists a $100 new-construction fee) alongside the building permit, and "SE" in SR, where the Board of Zoning Appeals must hold a published public hearing, make six written findings, and grant only with the concurring vote of four of its five members (§§1321.10, 1321.11). MUC and MIN leave the cell blank, which §1327.03(b)(3) makes a prohibited use. Lots in the Historic Preservation Overlay also need a Certificate of Appropriateness from the Historic Preservation Review Commission for exterior work. From 1-1-2027 W. Va. Code §8-42-1(b) and §8-42-2(a) require approval by right, with no special exception or public hearing, on every single-family lot, and §8-42-3(b) caps the ADU application fee at $250 plus usual building fees.

§1327.08(b)(1)(B) and (C) tie the ADU to the owner's family: the owner must be related to at least one adult living in the unit, and occupancy is capped at one adult with related minor children or two adults with minor children related to one of them, so the unit cannot be let to an unrelated household; a separate street number for it is prohibited (§1327.08(b)(1)(G)). Any dwelling unit let for rent or other consideration must be registered and pass a health-and-safety inspection under Article 1781 as replaced by Ord. 2026-05 (third and final reading 4-21-2026; $25 registration fee per unit per cycle and a $50 fee for each city inspection). Short-term rental of the ADU is blocked by the same occupancy rule, although Tourist Home (whole-building transient lodging) and owner-occupied Bed and Breakfast are by-right principal uses in all six mapped districts, and the use table's footnotes recite W. Va. Code §8-1-5a(k), under which municipalities "may not prohibit or effectively limit the rental of a property". From 1-1-2027 §8-42-2(d)(3) voids the family-relationship requirement, opening the ADU to ordinary registered rentals, while §8-42-3(a) preserves the city's power to regulate short-term rentals.