Dallas Accessory Dwelling Unit (ADU) Regulations
The City of Dallas permits the construction and rental of Accessory Dwelling Units (ADUs) on single-family building sites either through the establishment of an Accessory Dwelling Unit Overlay or by obtaining a special exception from the Board of Adjustment. These secondary dwellings must remain subordinate to the primary structure, and the City of Dallas requires the property owner to reside in either the main house or the ADU during any tenancy. Most residential building sites in the City of Dallas require at least one additional off-street parking space for an ADU, though this is waived if the property is within 1,200 feet of a DART bus or transit stop.
General Overview of Accessory Dwelling Units
An Accessory Dwelling Unit is defined by the City of Dallas as a rentable additional dwelling unit that is subordinate to the main unit and located on a building site currently used for single-family purposes [Section 51A-4.510]. Under the Dallas Development Code, these units can be attached to the primary residence or constructed as a detached structure. The City of Dallas prohibits an Accessory Dwelling Unit from being sold separately from the main building on the lot [Section 51A-4.510].
Dimensional and Placement Standards
The City of Dallas enforces specific size and placement requirements to ensure ADUs remain compatible with existing single-family neighborhoods.
| Category | City of Dallas Standard |
|---|---|
| Minimum Floor Area (Detached) | 200 square feet |
| Maximum Floor Area (Detached) | The greater of 700 square feet or 25% of the main structure |
| Maximum Floor Area (Attached) | The greater of 700 square feet or 25% of the main use |
| Maximum Height | Cannot exceed the height of the main dwelling unit |
| Location | Prohibited in front of the main structure |
| Minimum Side Yard Setback | 3 feet (if structure is < 15 feet tall and in the rear 30% of the lot) |
| Minimum Rear Yard Setback | 3 feet (if structure is < 15 feet tall and in the rear 30% of the lot) |
For any structure 15 feet or taller containing an Accessory Dwelling Unit, the City of Dallas requires compliance with the standard side and rear yard setbacks of the property's base zoning [Section 51A-4.510].
Parking and Utility Requirements
The City of Dallas generally requires one off-street parking space for an Accessory Dwelling Unit in addition to the parking required for the primary residence. However, the City of Dallas does not require this additional space if the building site is located within 1,200 feet of a DART bus or transit stop [Section 51A-4.510]. Regarding utilities, a building site in the City of Dallas with an ADU may be supplied by up to two electrical utility services and metered by two separate electrical meters [Section 51A-4.510].
Occupancy and Rental Regulations
The City of Dallas mandates that the property owner must reside on-site, occupying either the primary dwelling or the Accessory Dwelling Unit, if the ADU is used as rental accommodation. An owner may be absent for up to one year with approval from the director [Section 51A-4.510]. Additionally, any rentable Accessory Dwelling Unit in the City of Dallas must be registered with the city's single-family non-owner occupied rental program [Section 51A-4.510].
Board of Adjustment Special Exceptions
In areas where an Accessory Dwelling Unit Overlay has not been established, the City of Dallas Board of Adjustment may grant a special exception to authorize an ADU. The Board of Adjustment must determine that the unit will not adversely affect neighboring properties. If the Board of Adjustment grants this exception, they will require the applicant to deed restrict the property to prevent the ADU from being sold as a separate entity and to ensure the property remains owner-occupied [Section 51A-4.209].
The Accessory Dwelling Unit Overlay Process
Neighborhoods in the City of Dallas may petition to create an Accessory Dwelling Unit Overlay. This process requires:
- A proposed overlay area containing at least 50 single-family structures.
- A neighborhood meeting conducted by the City of Dallas.
- A petition signed by the owners of at least 50 percent of the lots within the proposed overlay [Section 51A-4.510].
Sections Cited
- Sec. 51A-2.102
- Sec. 51A-4.209
- Sec. 51A-4.510
- Sec. 51A-4.701
- Sec. 51A-4.704