Charlotte, NC Accessory Structures: ADU Rules (2026)

Charlotte's UDO (effective June 1, 2023) treats an accessory dwelling unit as a complete, separate dwelling unit with its own cooking and sanitary facilities. The ADU may be within or attached to the principal dwelling, or located within a detached accessory structure such as a garage. Per UDO use standards, only one ADU is permitted per lot containing a single-family or qualifying duplex residential use, and the ADU must be clearly subordinate to the principal residential use. Both units must be held under common ownership. The ADU cannot be served by a driveway separate from the one serving the principal dwelling, except where the lot is a corner lot, a through lot abutting two parallel local public streets, or abuts an alley - in those cases, a separate driveway may be provided from the side street, the local public street with reverse frontage, or the alley. Detached ADU floor area is capped at the lesser of 50% of the principal dwelling's floor area or 1,000 heated square feet. Accessory structures, including ADUs, must also comply with general accessory-structure standards in UDO Article 17 (setbacks, height, and lot coverage tied to the underlying zoning district). State enabling authority for the UDO comes from NCGS Chapter 160D. ADUs must meet the NC Residential Code for construction and require building, electrical, plumbing, and mechanical permits through Charlotte Development Services.