Zoning & Size Limits
| Requirement | San Jose, CA | Sacramento, CA |
|---|
| Allowed Zones | All residential zones (R-1, R-2, R-M, R-MH) | R-1, R-1A, R-1B, R-2, R-2A, R-2B, R-3, R-4, R-5 zones |
| Max Size (Detached) | 1,200 sq ft | 1,200 sq ft |
| Max Size (Attached) | 1,200 sq ft or 50% of primary dwelling | 1,200 sq ft or 50% of primary dwelling |
| Max Height | 25 ft for detached | 25 ft |
| Parking Required | No parking required | No parking required |
| Owner Occupancy | Not required | Not required |
Setback Requirements
| Setback | San Jose, CA | Sacramento, CA |
|---|
| Rear Setback | 4 ft | 4 ft |
| Side Setback | 4 ft | 4 ft |
| Front Setback | Per underlying zone | Per underlying zone |
Permits & Timeline
| Detail | San Jose, CA | Sacramento, CA |
|---|
| Permit Timeline | 60 days | 60 days |
| Permit Fees | $4,000-$14,000 | $3,000-$10,000 |
| Impact Fees | Waived for units under 750 sq ft | Waived for units under 750 sq ft |
| Pre-Approved Plans | Limited pre-approved options available | Yes — city offers pre-approved ADU plans |
Construction Costs
| Cost | San Jose, CA | Sacramento, CA |
|---|
| Avg Build Cost | $180,000-$400,000 | $100,000-$250,000 |
| Cost Per Sq Ft | $250-$450 | $150-$300 |
| Garage Conversion | $100,000-$220,000 | $60,000-$140,000 |
| Prefab ADU | $130,000-$300,000 | $80,000-$200,000 |
Rental Income Potential
| Rental | San Jose, CA | Sacramento, CA |
|---|
| 1BR Avg Rent | $2,000-$2,800/mo | $1,300-$1,800/mo |
| 2BR Avg Rent | $2,500-$3,500/mo | $1,600-$2,200/mo |
| Short-Term Rentals | Restricted; requires transient occupancy tax registration | Allowed with permit in certain zones |
| Est. ROI | 5-9% annual return | 8-12% annual return |
Which City Is Better for ADUs?
San Jose scores 8/10 while Sacramento scores 8/10 on our ADU-friendliness index.
Both cities offer viable ADU development opportunities — the best choice depends on your specific property, budget, and goals.
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