ADU rules in Texas
Representative cities: Houston, Dallas, Austin.
ADU permit rule
Permit requiredRestrictedcity authority
Fee basis
Permit and plan-review fees set by the city. Verify with the local building department.
Typical timeline
Varies by city; 2–8 weeks.
Setback
Per local zoning.
Area threshold
Allowed only where the local ordinance permits.
Exempt if
None — where allowed, ADUs require a permit.
Go / no-go
restricted
Texas has no statewide ADU mandate; ADUs are allowed only where the local ordinance permits (e.g., Austin, Houston, Dallas). Zoning, size caps, and parking rules apply.
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Frequently asked questions
Do I need a permit to build an ADU in Texas?
Per Texas rules, an ADU is "yes" for a permit and the authority is "city". Texas has no statewide ADU mandate; ADUs are allowed only where the local ordinance permits (e.g., Austin, Houston, Dallas). Zoning, size caps, and parking rules apply. Always confirm with the issuing building department.
How big can an ADU be in Texas?
Area threshold: Allowed only where the local ordinance permits.
What are the ADU setbacks in Texas?
Setback: Per local zoning.
How much does an ADU permit cost in Texas?
Fee basis: Permit and plan-review fees set by the city. Verify with the local building department.
State-wide sources: TX Dept. of Licensing & Regulation — Building Codes (state building authority) · City of Austin Development Services — Residential Plan Review
Plan the ADU numbers for Texas
ADU build cost calculator
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Rental ROI and payback
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Financing comparison
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Does your ADU need a permit?
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