West Durham

Durham County, NC (333,000 residents including the City of Durham) operates the City-County Joint Planning Department. The Durham Unified Development Ordinance (UDO) governs zoning across both the city and the county. ADUs (the UDO uses "accessory dwelling unit") are permitted in many residential districts subject to size, lot, and setback conditions.

• Durham Unified Development Ordinance
• N.C.G.S. Ch. 160D

State-floor overlay: NC Ch. 160D framework.

Durham County administers flood-hazard, and (where mapped) coastal, wildland-fire, historic, and airport overlays that shape ADU project feasibility. The most consistent overlay across the county is FEMA NFIP floodplain regulation; other overlays apply to specific geographies inside the county.

• FEMA NFIP Special Flood Hazard Areas in Durham County — A new ADU in a mapped SFHA must be elevated to or above the Base Flood Elevation; cost impact on the project is often material.
• Historic districts and individually-listed historic resources

Durham County issues building permits for parcels in unincorporated territory through its development services / planning department, with separate review tracks for zoning conformance, building-code compliance, on-site sewage where applicable, floodplain compliance, and addressing. Inside incorporated municipalities, city departments handle their own permits; the county's authority is geographically limited to unincorporated territory. An ADU permit application is typically processed as a residential building permit with a zoning verification step against the county's ordinance for the parcel's zoning district.