Zoning & Size Limits
| Requirement | Austin, TX | Dallas, TX |
|---|
| Allowed Zones | SF3, SF2, SF1, MU, UR, etc. | Single-family residential — but ADUs are generally NOT by-ri |
| Max Size (Detached) | Lesser of 1,100 sq ft or 15% of lot area (HOME Initiative). 2nd-story floor area capped at 550 sq ft. | 800 sq ft (Dallas caps ADUs at 800 sq ft) |
| Max Size (Attached) | Lesser of 1,100 sq ft or 15% of lot area (HOME Initiative) | Greater of 700 sq ft or 25% of the main dwelling's floor area (Dallas City Code §51A-4.510) |
| Max Height | 30 feet (2 stories typical under HOME) | 35 feet |
| Parking Required | No off-street parking required for ADUs under 550 sq ft; 1 s | Confirm with Dallas Planning & Development — an additional o |
| Owner Occupancy | Not required | Required — either the primary dwelling or the ADU must be ow |
Setback Requirements
| Setback | Austin, TX | Dallas, TX |
|---|
| Rear Setback | 10 feet | 15 feet |
| Side Setback | 5 feet | 5 feet |
| Front Setback | 25 feet | 20 feet |
Permits & Timeline
| Detail | Austin, TX | Dallas, TX |
|---|
| Permit Timeline | Confirm with Austin Development Services Department (typical 45-90 days) | 50-75 days |
| Permit Fees | $2,500-$4,000 | $2,200-$3,800 |
| Impact Fees | $1,200-$2,000 | $900-$1,600 |
| Pre-Approved Plans | City offers expedited review for pre-approved plan | Available for detached ADUs |
Construction Costs
| Cost | Austin, TX | Dallas, TX |
|---|
| Avg Build Cost | $125,000-$250,000 | $115,000-$230,000 |
| Cost Per Sq Ft | $165-$330 | $130-$250 |
| Garage Conversion | $60,000-$140,000 | $55,000-$135,000 |
| Prefab ADU | $85,000-$200,000 | $80,000-$185,000 |
Rental Income Potential
| Rental | Austin, TX | Dallas, TX |
|---|
| 1BR Avg Rent | $1,300-$1,900/mo | $1,150-$1,700/mo |
| 2BR Avg Rent | $1,700-$2,500/mo | $1,450-$2,200/mo |
| Short-Term Rentals | Check local restrictions | Not permitted in most areas |
| Est. ROI | 7-10% annual return | 6-8% annual return |
Which City Is Better for ADUs?
Austin scores 8/10 while Dallas scores 6/10 on our ADU-friendliness index.
Austin edges ahead overall. Both cities offer viable ADU development opportunities — the best choice depends on your specific property, budget, and goals.
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