Durham's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Durham, North Carolina, there are 3 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

Shed & Carport Rules

A backyard shed in Durham is regulated as an 'accessory structure' under UDO § 5.4.1, jointly administered by Durham City-County Planning within the city limits. It can't be larger than the primary house, must sit behind the front building line, and needs at least a five-foot side/rear setback in most residential districts. Height is capped at two stories/32 feet or the house's own height, whichever is greater.

Key details: Max size: cannot exceed footprint of primary structure. Standard setback: 5 ft rear/side (3 ft in RU/RC districts). Max height: 2 stories/32 ft, or house height if taller. Flood zone cap: 1,000 sq ft, no habitation. Administered by: Durham City-County Planning (joint UDO).

A shed that violates size, setback, or height standards is a zoning violation enforced by Durham City-County Planning, which can order the structure relocated, resized, or removed as a condition of compliance before other permits or approvals will issue on the property. That is separate from the misdemeanor exposure under Sec. 10-48 if the shed also went up without a required building permit.

ADU Rules

Durham's UDO lets one accessory dwelling unit onto most residential lots under Sec. 5.4.2 without added parking. A standard ADU is capped at 1,000 square feet on a single story and 1,200 heated square feet total, RR District lots of four-plus acres can go up to 50% of the primary home's area, and a travel trailer or RV can't serve as an ADU except for stays of two weeks or less.

Key details: ADUs per lot: one, on a 1- or 2-unit lot. Size cap: 1,000 sf single story / 1,200 sf heated. RR District large lots: up to 50% of primary home's area. Parking: none required for an ADU. Flood zones: ADUs barred from Special Flood Hazard Areas.

An accessory dwelling that exceeds the 1,000/1,200-square-foot floor-area caps, that adds a second ADU to a lot already at its one-unit limit, that sits in a Special Flood Hazard Area, or that uses a travel trailer or RV beyond the two-week visit exception is a zoning violation under Sec. 5.4.2, enforced by the Durham Inspections Department through UDO Article 15's notice-and-correction process.

Garage Conversions

Durham's Unified Development Ordinance exempts accessory dwelling units from height limits when they are created by converting existing space inside the primary house, such as a garage, rather than adding new construction. The heated floor area is capped at 1,000 square feet on a single story or 1,200 square feet total, and can never equal or exceed the primary home's own floor area.

Key details: Governing section: UDO § 5.4.2, Accessory Dwellings. Height exemption: Waived for conversions of existing space within the house. Size cap: 1,000 sq ft single story / 1,200 sq ft total. RR district cap: 50% of primary home's floor area on 4+ acre lots. Civil penalty: $500 per violation, daily for continuing violations.

An ADU built or converted without following UDO § 5.4.2 is a zoning violation enforced under UDO Article 15. The City-County Planning Director can issue a notice of violation and a citation carrying a $500 civil penalty per violation, with continuing violations assessed daily until corrected. Owners can cure the violation by meeting the standard, obtaining a variance under § 3.14, or amending the ordinance; unresolved cases can be referred for injunctive relief in Superior Court.

The Bottom Line

Durham's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Durham is broadly strict or permissive.

Keep in mind that Durham can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.