ADU rules in Jefferson County

A detached ADU is allowed in two forms under Section 8.15, both approved administratively. An In-Law Suite (a unit housing a relative of the owner) may be detached only on a property of at least two acres (§8.15A(b)), and Appendix C makes it a permitted use in the Rural (R), Rural Residential (RR), Residential Growth (RG), Residential-Light Industrial-Commercial (R-LI-C), Residential Commercial (RC), Village (V) and Planned Neighborhood Development (PND) districts. An Accessory Agricultural Dwelling Unit, listed as permitted in every district, needs a property of at least ten acres whose primary use is agricultural and is limited to a farmworker or caretaker and family (§8.15B). Both types need Health Department approval, which in practice turns on septic and well capacity on unsewered rural lots.

Section 8.15 says an ADU 'may be attached to the principal dwelling unit or detached', and the two-acre minimum applies only to detached In-Law Suites, so an attached or internal unit (an addition, basement or conversion with its own kitchen, bathroom and sleeping area) is available on any lot in the seven districts where In-Law Suites are permitted. What makes it conditional is occupancy: the unit is limited to a relative of the owner (blood, marriage or adoption), the owner or an immediate family member must live in one of the two units, and the Health Department must approve it. In-Law Suites are not permitted in the NC, GC, HC, LI, MI, OC and IC districts (Appendix C).

Section 8.15A(a) requires an In-Law Suite to be 'Secondary in size to the principal dwelling unit, with a maximum size of 1,700 heated square feet, gross floor area', and §8.15B(a) sets the same 1,700 sq ft cap for an Accessory Agricultural Dwelling Unit. There is no percentage-of-house figure beyond being smaller than the principal dwelling, and no ADU-specific height limit; the district site development standards in Appendix A apply. The Board of Zoning Appeals grants size variances case by case: 1,984 sq ft on 10-23-2025 (File 25-29-ZV) and 2,738 sq ft on 7-23-2026 (File 26-19-ZV), both on Rural parcels of more than ten acres.

The Section 2.2 definition and the opening paragraph of Section 8.15 both state that 'The property owner or immediate family member must occupy either the principal dwelling unit or the accessory dwelling unit', and that the owner of the ADU is the owner of the principal dwelling. The rule is ongoing, part of what the use is, not a one-time test at application, and the footnote to §8.15A repeats it even where the BZA has allowed rental to non-relatives. An immediate family member of the owner can satisfy it in the owner's place. No state law preempts it: W. Va. Code §8-42 governs municipalities only and does not bar owner occupancy in any case.

Section 8.15A(d) lists 'Sufficient parking available' among the In-Law Suite criteria without a number, and staff judge it from the zoning certificate sketch, which must show the number and location of existing and proposed parking spaces. Section 11.2's residential parking table sets 'Driveway Only' for a single-family detached dwelling and has no entry for an accessory dwelling unit. The Accessory Agricultural Dwelling Unit criteria in §8.15B contain no parking clause.

Section 8.15 provides that 'One of each type of Accessory Dwelling Unit as defined in this section may be permitted administratively for each property', and Appendix C marks both types 'P'. Approval is a zoning certificate from the Zoning Administrator, due within 60 days of a complete application (§3.2C and F; the county's Zoning Certificate Application lists 'Accessory Dwelling Unit' as a certificate type), together with a building permit and Health Department approval. A second unit of the same type needs a Board of Zoning Appeals special exception after a public hearing (§8.15, §6.5; File 24-1-SE was approved 4-25-2024), as does rental to non-relatives, and a unit over 1,700 sq ft needs a BZA variance. A lot whose recorded plat carries a single-family restriction note also needs a Planning Commission Final Plat Amendment, heard in public, before the ADU can be built.

The footnote to §8.15A reads 'Should relative no longer require the use of the Accessory Dwelling Unit, the property owner may apply for a Special Exception before the Board of Zoning Appeals to allow for rental to non-relatives', so long-term rental to non-relatives is a discretionary approval after a hearing, and the owner or an immediate family member must still occupy one of the units; at an 11-10-2022 BZA hearing an applicant 'acknowledged that she would not be permitted to rent out the unit' (File 22-37-ZV). Section 8.16 permits a short-term rental (a dwelling unit offered to guests for periods under seven consecutive days, §2.2) anywhere a single-family dwelling is permitted, with a zoning certificate, off-street parking for the maximum number of occupants, a state business license and any required Health Department approval; because the In-Law Suite is limited to relatives, short-term rental of the ADU itself appears to need the same special exception. The ADU 'cannot be bought or sold separately unless subdivided'. W. Va. Code §8-1-5a(k), which bars Home Rule municipalities from limiting rentals, does not apply to counties.