ADU laws in North Carolina

In plain words

North Carolina now has a statewide ADU law, but it only reaches larger cities. An ADU, or accessory dwelling unit, is a small second home on the same lot as a house. It can be attached to the house or stand on its own in the yard. Zoning is the local rulebook for what can be built where. A 2026 law covers cities and towns with at least 50,000 people. They must allow one ADU next to each single-family home in residential zones. Cities in the 20 coastal counties are left out. So are smaller towns and land outside city limits. The rule starts January 15, 2027. Covered cities have until July 1, 2027 to update their codes, or ADUs are allowed there without limits. In covered cities, the city cannot demand extra parking. It cannot charge more than it would for a similar house permit. It also cannot stop you from renting both homes to long-term tenants. So you do not have to live on site. The city can still cap the ADU's size somewhere between 800 and 1,000 square feet. It can ask that the ADU sit beside or behind the house. It can require a setback of up to 10 feet. A setback is the open space required between a building and the property line. The law skips historic districts and HOA or deed rules. It also skips units without water and sewer or well and septic. A separate law ends minimum parking counts in most of the state in 2027. Everywhere else, your town or county still decides. You can build only if local rules and your property allow it.

The rules at a glance

What to do next

1. Find out whether your property is inside the limits of a city or town with 50,000+ people and outside the 20 coastal-area counties; your county GIS map or city planning office can confirm.
2. Read your deed and any HOA covenants; the state ADU law does not override private restrictions that ban second units.
3. Ask your city or county planning department for its current ADU rules, and if your city is covered, ask how and when it will update its code before July 1, 2027.
4. Confirm utility capacity: ask your water and sewer provider, or your county health department if you are on a well or septic system, whether the property can serve a second unit.
5. If your home is in a local historic district, start with the historic preservation commission, since the state mandate does not apply there.
6. Work with a designer or builder who knows the NC Residential Code, and get permits before any work starts.

What your town still decides

North Carolina cities and counties regulate land use under G.S. Chapter 160D. Outside the covered cities, each town or county still decides whether ADUs are allowed, in which zones, at what size, and whether the owner must live on site. A few statewide rules apply everywhere: temporary health care structures (G.S. 160D-915), no minimum building size for houses under the Residential Code, and, from 2027, no minimum parking counts outside the coast. The new ADU mandate does not override private covenants or HOA rules, and it does not apply in local historic preservation districts, at National Historic Landmarks, or to units without water and sewer or well and septic. A covered city whose code already meets the law does not need to re-adopt. There are no state ADU grant or loan programs; Charlotte and Durham have run city-funded affordable-ADU loan programs, both now closed to new applicants.

Examples of local rules

• Charlotte: The Unified Development Ordinance allows one ADU per lot alongside a single-family home or a duplex that is not on a sublot. The ADU must stay under the same ownership as the main home, and owners may rent it. The city's Queen City ADU forgivable-loan program (up to $80,000 for affordable rentals) stopped taking applications on October 31, 2025. Source
• Raleigh: ADUs can be detached, attached, internal, over a garage or in a basement. Generally one per lot; two are allowed only on parcels in a Frequent Transit Area. Detached ADUs follow the new single-family home permit process, and the city offers pre-reviewed 'Fast Track' plans at low cost. Source
• Durham: UDO Sec. 5.4.2 allows one ADU on a residential lot with one or two main units, up to 1,000 square feet on one floor and 1,200 square feet total. No parking is required and the code sets no owner-occupancy rule. ADUs are not allowed in flood hazard areas. The city's 2% affordable-ADU loan pilot is fully committed and closed. Source
• Asheville: One ADU is usually allowed on a residential lot with a single-family home. Size is capped at 800 square feet on lots under one acre and 1,200 square feet on lots of one to three acres. In January 2026 the council let owners convert older accessory buildings that sit too close to the property line without a variance; ADUs created that way cannot be used as short-term vacation rentals or homestays. Source

What we’re still confirming

• Which cities have 50,000 or more people under the law depends on which population count the state uses; ask your city whether it's covered.
• The law bars requiring a rezoning for an ADU, but whether a covered city can still require a special use permit with a hearing hasn't been tested.

Laws, bills and citations

This is general information, not legal advice. Your town, village, city or county decides what can be built on your property. If something here looks out of date, email the team.