Wicomico County, MD Accessory Structures: ADU Owner Occupancy (2026)

Wicomico County's zoning code treats an accessory apartment (commonly called an ADU or in-law suite) as a use permitted only where the owner lives in the main house. B, an accessory apartment is 'not more than one apartment unit as an accessory use within an owner-occupied single-family residence or an accessory building on the same lot,' and the parcel must measure at least 20,000 square feet. The unit cannot exceed 50% of the principal residence's square footage, its parking must be sited as the Board of Appeals directs, and a lot that has already exercised the option to rent out guest rooms may not add an accessory apartment on top of that.

Section 225-60 sets the approval path: the county allows only one accessory apartment per lot, and it is permitted solely as a special exception on a lot holding a detached single-family or two-family dwelling, meaning an applicant must go before the Board of Appeals before building or renting one out. An accessory apartment is barred outright on any site already running a Type II or Type III home-based business. Attached units must match the principal dwelling's exterior finish, roof pitch, trim, windows and eave projection, and only one street-facing entrance is allowed unless the house already had more than one.

Detached units face their own site rules: a 60-foot front setback (or 85 feet from the road's center line, whichever is greater), a six-foot setback behind the principal dwelling, the district's standard side and rear setbacks, a footprint no larger than the principal dwelling's, and a 25% cap on the combined footprint of all detached accessory structures on the lot.