Charlotte Accessory Dwelling Unit (ADU) Development Standards
In the City of Charlotte, one Accessory Dwelling Unit (ADU) is permitted per lot as a subordinate use to a single-family or duplex dwelling, provided the ADU remains under the same ownership as the principal structure. Accessory Dwelling Units located within a separate accessory structure are restricted to a maximum of 1,000 heated square feet and must be situated at least five feet from the principal building. The City of Charlotte Unified Development Ordinance (UDO) prohibits the use of recreational vehicles, campers, or trailers as ADUs and generally requires the unit to share a driveway with the primary residence [Section 15.3, Section 15.6.F].
General Overview and Definitions
The City of Charlotte defines an Accessory Dwelling Unit (ADU) as an additional dwelling unit that is both associated with and incidental to a principal dwelling. To qualify as a legal unit under the City of Charlotte UDO, the ADU must include its own separate cooking and sanitary facilities. The ordinance explicitly states that recreational vehicles, travel trailers, campers, or any other type of motor vehicle cannot serve as an ADU [Section 15.3].
Permitted Zoning Districts
According to the City of Charlotte Global Use Matrix, ADUs are allowed with "Prescribed Conditions" (PC) in nearly every residential, commercial, and campus district, including:
- Neighborhood 1 Zoning Districts: N1-A, N1-B, N1-C, N1-D, N1-E, N1-F.
- Neighborhood 2 Zoning Districts: N2-A, N2-B, N2-C.
- Employment and Centers Districts: CG, CR, IC-1, IC-2, OFC, OG, RC, IMU, NC, CAC-1, CAC-2, RAC, UC, UE.
- Transit Oriented Development Districts: TOD-UC, TOD-NC, TOD-CC, TOD-TR.
- Special Districts: MHP (Manufactured Home Park) [Section 15.2].
Prescribed Conditions for ADUs
The City of Charlotte UDO imposes specific regulations to ensure the ADU remains a secondary use of the property. These conditions apply regardless of the base zoning district.
Quantity and Ownership
Only one ADU is permitted per lot in the City of Charlotte. Both the ADU and the associated principal dwelling must remain under the same ownership [Section 15.6.F.3, 15.6.F.4].
Placement and Size
If the ADU is built as part of a detached accessory structure, it is subject to specific size limitations based on the dimensions of the principal residential use.
| Standard | Requirement |
|---|---|
| Maximum Units per Lot | 1 Unit [Section 15.6.F.3] |
| Minimum Separation | 5 feet from the principal structure [Section 17.1.E.3] |
| Maximum Size (General) | Whichever is greater: 600 heated sq. ft. OR 70% of the total floor area of the principal use [Section 15.6.F.6.a] |
| Absolute Maximum Size | 1,000 heated sq. ft. [Section 15.6.F.6.a] |
Driveways and Access
The City of Charlotte requires that the ADU be served by the same driveway as the principal dwelling. However, the City of Charlotte UDO allows for a separate driveway in the following specific circumstances:
- The lot is a corner lot.
- The lot is a through lot abutting two parallel local public streets.
- The lot abuts an alley [Section 15.6.F.5].
Siting and Setback Requirements
As accessory structures, ADUs must comply with the general locational requirements of Article 17 in the City of Charlotte UDO.
Prohibited Locations
In the City of Charlotte, no accessory structure (including ADUs) is permitted within the established front or corner side setback along a street or frontage. An exception exists for single-family detached dwellings on large lots: if the primary house is set back at least 150 feet from the right-of-way, an ADU may be placed in the front yard if it is at least 50 feet from the right-of-way [Section 17.1.E.1].
Side and Rear Setbacks
The required distance from property lines depends on the height of the ADU structure.
| Structure Height | Side Setback | Rear Setback |
|---|---|---|
| Under 24 Feet | Minimum 3 feet | Minimum 3 feet |
| 24 Feet or Taller | Same as the required side setback for the base district | Minimum 15 feet |
Note: Siting is measured from the lot line to the closest component of the structure [Section 17.1.E.2].
Building and Design Standards
ADUs in the City of Charlotte must be clearly subordinate to the principal residential use. If an ADU is built in conjunction with a duplex, it is only permitted if each unit of the duplex is not located on a sublot [Section 15.6.F.2]. Architectural features like sills, eaves, and cornices may extend up to 3 feet into required setbacks, provided they maintain a minimum vertical clearance of 9 feet [Section 18.2.C.4].
Sections Cited
- Section 2.2 General Abbreviations
- Section 15.2 Global Use Matrix
- Section 15.3 Use Definitions
- Section 15.6.F Prescribed Conditions for Accessory Dwelling Units
- Section 17.1 General Standards for Accessory Structures
- Section 17.2 Standards for Specific Accessory Structures
- Section 18.2 Architectural Features