Zoning & Size Limits
| Requirement | Dallas, TX | San Antonio, TX |
| Allowed Zones | Single-family residential (SF) | Selected residential zones only |
| Max Size (Detached) | 900 sq ft | 800 sq ft |
| Max Size (Attached) | 700 sq ft | Not typically allowed |
| Max Height | 35 feet | 30 feet |
| Parking Required | 1 space per primary unit + 1 for ADU | 2 spaces |
| Owner Occupancy | Not required | Not required |
Setback Requirements
| Setback | Dallas, TX | San Antonio, TX |
| Rear Setback | 15 feet | 20 feet |
| Side Setback | 5 feet | 5 feet |
| Front Setback | 20 feet | 25 feet |
Permits & Timeline
| Detail | Dallas, TX | San Antonio, TX |
| Permit Timeline | 50-75 days | 90-120 days |
| Permit Fees | $2,200-$3,800 | $4,000-$6,500 |
| Impact Fees | $900-$1,600 | $1,200-$2,200 |
| Pre-Approved Plans | Available for detached ADUs | Not available |
Construction Costs
| Cost | Dallas, TX | San Antonio, TX |
| Avg Build Cost | $115,000-$230,000 | $110,000-$220,000 |
| Cost Per Sq Ft | $130-$250 | $140-$275 |
| Garage Conversion | $55,000-$135,000 | $50,000-$130,000 |
| Prefab ADU | $80,000-$185,000 | $75,000-$170,000 |
Rental Income Potential
| Rental | Dallas, TX | San Antonio, TX |
| 1BR Avg Rent | $1,150-$1,700/mo | $1,050-$1,550/mo |
| 2BR Avg Rent | $1,450-$2,200/mo | $1,300-$1,950/mo |
| Short-Term Rentals | Not permitted in most areas | Not permitted |
| Est. ROI | 6-8% annual return | 5-7% annual return |
Which City Is Better for ADUs?
Dallas scores 6/10 while San Antonio scores 5/10 on our ADU-friendliness index.
Dallas edges ahead overall. Both cities offer viable ADU development opportunities — the best choice depends on your specific property, budget, and goals.
Finance Your ADU Project
Most ADU projects are funded through HELOCs, construction loans, or cash-out refinancing. Compare rates from top lenders.
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