Quick Answer
Houston ADUs: $150K–$300K
Permits: $1,000–$5,000 · Updated April 2026
Detailed Cost Breakdown
| Category | Cost Range |
|---|---|
| Design & Architecture | $8,000–$20,000 |
| Permits & Fees | $1,000–$5,000 |
| Site Preparation | $8,000–$18,000 |
| Foundation | $15,000–$35,000 |
| Framing & Exterior | $30,000–$60,000 |
| Mechanical (HVAC/Plumbing/Electrical) | $25,000–$50,000 |
| Interior Finishes | $20,000–$40,000 |
| Landscaping & Drainage | $5,000–$15,000 |
Costs based on a typical 500–800 sf ADU in the Houston metro area (2026 estimates).
Timeline & Permits
6–12 weeks
Permit Timeline
$1,000–$5,000
Total Permit Costs
900 sf
Max ADU Size
Track Every Dollar of Your ADU Build
TerraLine is the construction finance cockpit that shows your loan balance, budget burn, and forecast at completion — all on one screen. No more spreadsheets.
Houston ADU Regulations
- Houston has NO traditional zoning — but deed restrictions may prohibit ADUs. Check your deed first
- Max ADU size: 900 sf in city regulations
- 5 ft minimum setbacks from side and rear property lines
- Stormwater detention may be required in flood-prone areas
- Free pre-approved ADU plans available from the City of Houston ('Double House')
- No owner-occupancy requirement — investor-friendly
Climate & Construction Notes
Houston's extreme humidity, heavy rainfall, and flood risk require elevated foundations, robust drainage systems, and moisture-resistant construction throughout. High-efficiency AC is essential for the 7+ month cooling season.
Rental Income Potential
Studio/1BR ADU rent in Houston: $1,080–$1,300/month
Frequently Asked Questions
How much does it cost to build an ADU in Houston?
A typical 500–800 sf ADU in Houston costs $150K–$300K ($200–$350/sf). This includes design, permits, construction, and finishes. Actual costs depend on ADU type, lot conditions, and finish level.
What are ADU permit costs in Houston?
Permit and fee costs range from $1,000–$5,000. The permit timeline is typically 6–12 weeks. Types allowed: detached, attached, garage conversion.
Is owner-occupancy required for Houston ADUs?
No. Always verify current regulations with your local planning department before starting your project.
Finance Your Houston ADU
Compare HELOC, construction-perm, DSCR, and renovation loans. See the full ADU financing guide, run the loan calculator, or estimate your build with the free cost estimator.