What's Required in Dallas
- A second dwelling unit on a single-family lot needs a Board of Adjustment special exception first.
- The board must find the unit will not be rented and will not adversely affect neighboring properties.
- The owner must record a deed restriction preventing rental of the additional dwelling unit.
- In districts such as R-7.5(A), an accessory structure may not exceed 25 percent of the main structure floor area.
- Building permit fees are set by square footage under Chapter 52 Table A-I, not by construction cost.
- Full construction plans go through plan review, with a $577 minimum plan review fee.
- Garage conversions to living space require an energy code trade.
- The permit must be pulled by a registered contractor; homeowner permits do not cover ADUs.
Can you build an ADU in Dallas?
Yes, but in a single-family district not by right. Dallas zoning limits single-family lots to one dwelling unit, and a second unit, which the Dallas Development Code calls an additional dwelling unit, needs a special exception from the Board of Adjustment. Board case reports from 2026 quote the rule: under Section 51A-4.209(b)(6)(E)(i), the board may authorize an additional dwelling unit when, in its opinion, the unit will not be used as rental accommodations and will not adversely affect neighboring properties. Under (E)(ii), the board must require you to deed restrict the property so the unit cannot be rented. The applicant carries the burden of proof.
Size is the second gate. The same case files describe districts such as R-7.5(A), and R-5(A) within PD-595, as prohibiting an accessory structure larger than 25 percent of the floor area of the main structure, so a 2,000 square foot house supports a detached unit of up to 500 square feet without a further variance or special exception. In one 2026 case the application was filed on March 19 and heard on May 19.
How much does an ADU permit cost in Dallas?
Texas law bars value-based residential fees, so Dallas prices new single-family construction and additions by square footage on Chapter 52 Table A-I: $1.07 per square foot up to 700 square feet. The fee schedule effective July 1, 2025 adds a residential plan review fee of $0.046 per square foot or $577, whichever is greater, a $125 inspection fee per trade, and a $15 technology fee. The Board of Adjustment fee for a single-family special exception is $600, plus $10 per notification sign.
- 500 sq ft ADU, four trades: $535 + $577 + $500 + $15 = $1,627 in permit fees; $2,227 with the $600 Board fee.
- 700 sq ft ADU, four trades: $749 + $577 + $500 + $15 = $1,841; $2,441 with the Board fee.
- Planned development, specific-use-permit or deed-restricted lot: add 10 percent of the permit fee.
Water and wastewater service connections are a separate application with their own charges, which are not included here.
| What you are doing | City filing | Rule |
|---|---|---|
| Second dwelling unit on a single-family lot | Board of Adjustment special exception | Sec. 51A-4.209(b)(6)(E); not for rent, deed restricted |
| Renting the ADU out | Not permitted | The special exception requires a no-rental deed restriction |
| ADU over 25 percent of the house floor area | Additional Board relief | Accessory floor-area limit in districts such as R-7.5(A) |
| Building the new unit | Residential New Construction or addition permit | Table A-I square-footage fee plus plan review |
| Converting a garage to living space | Garage conversion permit | Energy code trade required |
| Homeowner building the ADU | Not allowed | Homeowner permit excludes new homes and additions |
| Lot in a planned development district | Check the PD ordinance | 10 percent surcharge on the permit fee |
Who can pull an ADU permit?
A registered contractor. The city’s homeowner exemption form says a homeowner permit does not allow you to build a new home, add on to an existing home, or build a permanent detached accessory building, which covers both attached and detached ADUs.
How to Get a ADU Permit in Dallas
Confirm zoning and size
Check your district and the 25 percent accessory floor-area limit against your house size before you design.
Apply to the Board of Adjustment
File the special exception application with the $600 fee, site plan and elevations; you must show the unit will not be rented or harm neighbors.
Record the deed restriction
If the board approves, record the no-rental deed restriction the approval requires.
Apply for the building permit
Your registered contractor files the permit in DallasNow with full plans, trades and the water and wastewater application.
Pay fees and build
Pay the square-footage permit, plan review, inspection and technology fees, then schedule inspections through final.