Cary, NC Accessory Structures: ADU Rules (2026)
ADU rules in Cary, NC, also called accessory dwelling unit regulations or granny flat ordinances, cover setbacks, owner-occupancy, parking, and permit requirements.
Key Facts
- Units allowed per lot
- 1
- Size cap (small lot)
- 800 sq ft or 50% of house
- Size cap (large lot, 40,000+ sf)
- 1,000 sq ft
- Parking required
- 1 off-street space
- Home occupation in ADU
- Prohibited
Summary
Cary allows one accessory dwelling unit per lot with a detached, single-unit home, capped in size and limited to one off-street parking space.
An accessory dwelling unit shall be permitted as an accessory use subject to the following standards: ... There shall be no more than one (1) accessory dwelling unit on a lot. ... At least one (1) off-street parking space shall be provided for an accessory dwelling unit. ... Home occupations shall be prohibited within an accessory dwelling unit.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2023 S-87_S-57: Current through local ordinance 2022-Code-05, passed 11-17-2022 and effective 11-17-2022 | LDO: Current through local ordinance 2022-LDO-04, passed 11-17-22 and effective 11-17-22).
Full Breakdown
The Town of Cary permits an accessory dwelling unit (ADU) as an accessory use to a principal detached dwelling in eligible residential and planned development districts. Only one ADU is allowed per lot. Heated floor area is capped at the lesser of 50% of the principal dwelling's heated floor area, or 800 sq. ft. (lots under 40,000 sq. ft.) or 1,000 sq. ft. (lots 40,000 sq. ft. or larger). At least one off-street parking space is required, home occupations are prohibited inside an ADU, and in the R-12, R-8, and TR districts a detached ADU cannot exceed the height of the principal dwelling.
Violations & Fines
Building an unpermitted ADU, exceeding the size cap, or adding a second ADU on the same lot is a zoning violation subject to enforcement by the Planning Department and correction or removal of the noncompliant structure.
Frequently Asked Questions
Can I rent out an ADU in Cary, NC?
Does Cary allow a detached ADU as tall as the main house?
Sources & Official References
Other rules in Cary
How Cary compares: Easiest Cities to Build an ADU·Compare Cary to another location·View the North Carolina accessory structures overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
ADU Rules in Nearby Cities
How other cities in Wake County handle adu rules.