The rules in one table
| Rule | What Raleigh says |
|---|---|
| Zoning | R-1, R-2, R-4, R-6, R-10, RX, OX, NX, DX and CX (ADU FAQ) |
| How many | One per lot; up to two in a Frequent Transit Area, only one of them attached |
| Size | 800 sq ft on lots up to 40,000 sq ft; 1,000 sq ft over 40,000; always smaller than the main house; all conditioned space counts |
| Height | 26 feet |
| Where on the lot (detached) | At or behind the front wall of the house; side and rear setbacks 5 ft on lots up to 40,000 sq ft, 10 ft on larger lots; 6 ft from other buildings |
| Alley | 4 ft from the alley without parking, 20 ft with parking |
| Parking | None required |
| Owner occupancy | Not required; the ADU cannot be sold apart from the house |
| Foundation | Permanent; no tiny homes on wheels (a manufactured-home ADU has its own rules, up to 600 sq ft) |
| Flag lots | Not allowed |
| Historic overlay | Follow the RHDC design guidelines and get a Certificate of Appropriateness before construction |
| HOA | The City says "Maybe": check your covenants |
Sources: UDO Sec. 2.6.3 and the City's ADU FAQs. If your house is in a historic overlay, see Raleigh historic district rules first.
The rule that decides who builds it
Raleigh's FAQ is blunt: "If you build the ADU yourself, you cannot rent it." An owner acting as builder must give the City a statement that the ADU will be built "solely as Not For Rent" before the permit is issued. The FAQ ties this to the owner exemption in G.S. 87-1.
If the ADU will be rented, or ever might be, you need a licensed North Carolina general contractor. The state threshold in G.S. 87-1 is $40,000 or more; Raleigh's FAQ quotes both $30,000 and $40,000 in different answers, so ask the Permit Helpline (919-996-2500) which figure it applies. The usual Raleigh ADU, filed at $112,256, is well over either line. Check the license on the NCLBGC search; our North Carolina license guide explains the limitation classes.
Which permit path
The City's ADU service page sends each type down a different process:
| ADU type | Raleigh process |
|---|---|
| New detached ADU | New Single-Family Dwelling process |
| Finishing an existing detached garage | ADU Change-of-Use |
| Attached ADU that adds square footage | Accessory Structure and Addition process |
| Converting space inside the house | ADU Change-of-Use |
| ADU on a duplex lot | Reviewed under the NC Commercial Code (an internal or attached one); one detached ADU allowed, making three units |
Raleigh also has a Fast Track gallery of ADU plans pre-reviewed for building code compliance, sold by their designers "at a fee far below the typical design cost". Fast Track ADUs still go through the new single-family dwelling process, so they save design time, not a permit.
What 139 Raleigh ADU permits show
| Measure | Raleigh ADU |
|---|---|
| Permits on homes, October 2023 to September 2026 | 139 |
| Firms on those permits | 102 |
| Firms active in the last 12 months | 49 |
| Usual filed value | $112,256 |
| Permits with a filed value | 97.8% |
| Firms with a single ADU permit | 79 (77.5%) |
| Most ADU permits in the last 12 months | Armature Design Build, 3 |
| Busiest / quietest month | April (193) / June (42) |
ADU building in Raleigh is a side line for almost everyone: 77.5% of the firms on these permits filed only one, and the busiest filed 3 in a year. Ask any builder for the address of an ADU it finished and look the permit up yourself in the City's portal (see Raleigh building permit search). Filed values by firm are on Raleigh ADU cost; new-house values for comparison are on Raleigh new home cost.
Compare Raleigh ADU builders by permits →
What this does not tell you
Raleigh's records in our file do not carry a reliable final-inspection date for ADUs, so we show no completion rate or build time. Filed values are construction estimates and leave out design, tap fees and site work. North Carolina contractor licenses are not matched in our Raleigh file, so check them on the state board's site. Setback figures above are the detached-ADU standards for single lots; townhouse lots and other districts (UDO Sec. 3.6.2) differ.
How we know this
Rules are quoted from the City of Raleigh's ADU FAQs, UDO Sec. 2.6.3 and the Building an ADU service page, read 23 October 2026, and G.S. 87-1 as published by the General Assembly. Permit counts are City of Raleigh permits on homes classified as ADUs, October 2023 to September 2026.
Numbers come from City of Raleigh building permits, data through October 12, 2026. Nobody paid to be on this page and nobody can.
Questions
- How big can an ADU be in Raleigh?
800 square feet of conditioned space on lots up to 40,000 square feet, and 1,000 square feet on lots over 40,000 (UDO Sec. 2.6.3). It must also be smaller than the main house, and the overall height limit is 26 feet.
- Do I need to live on the property to build an ADU in Raleigh?
UDO Sec. 2.6.3 has no owner-occupancy requirement. It does say the ADU cannot be sold or transferred apart from the main house.
- Can I build my own ADU in Raleigh and rent it?
No. The City's ADU FAQ says 'If you build the ADU yourself, you cannot rent it', and an owner-builder must sign a Not For Rent statement before the permit is issued. To rent it, hire a licensed NC general contractor.
- Can I have two ADUs in Raleigh?
Only in a Frequent Transit Area, where up to two are allowed and only one may be attached to the house. Everywhere else the limit is one ADU per lot, and ADUs are not allowed on flag lots.
- How much does an ADU cost in Raleigh?
The usual Raleigh ADU permit was filed at $112,256 (139 permits, October 2023 to September 2026). That is the construction value on the application, before design, utility connections and site work.
Build your own list
Every firm with that kind of permit on record. Pick what you value. The list moves.
Related guides
- Bellingham ADU rules under the 2025 interim ordinance: two per lot, 1,000 sq ft, no owner occupancy, and what ADU permits show
- Can an unpermitted ADU be legalized? California's AB 2533 rule, and what it costs and takes
- Denver ADU rules since citywide ADUs: owner occupancy, the licensed-contractor rule, and what ADU permits were filed at
- Do I need a permit for an ADU? Yes; here is what 9 cities require, and how long it takes
For one city
- ADU FAQs — City of Raleigh (updated 2026-07-14, accessed 2026-10-23)
- UDO Sec. 2.6.3 Accessory Dwelling — City of Raleigh (accessed 2026-10-23)
- Building an Accessory Dwelling Unit (ADU) — City of Raleigh (updated 2026-07-13, accessed 2026-10-23)
- NC General Statutes Chapter 87, Article 1 (G.S. 87-1) (accessed 2026-10-20)