Zoning & Size Limits
| Requirement | Vancouver, WA | Spokane, WA |
|---|
| Allowed Zones | Residential single-family zones | Single-family residential |
| Max Size (Detached) | 1,000 sq ft gross floor area | 1,000 sq ft |
| Max Size (Attached) | 1,000 sq ft gross floor area | 800 sq ft |
| Max Height | 35 feet | 35 feet |
| Parking Required | Not required within 1/2 mile of a major transit stop (per Wa | Studio and 1-bedroom ADUs: none required; larger units subje |
| Owner Occupancy | Not required | Not required (eliminated by Washington HB 1337), except when |
Setback Requirements
| Setback | Vancouver, WA | Spokane, WA |
|---|
| Rear Setback | Confirm with Vancouver Planning (VMC 20.810.040) | Confirm with Spokane Planning (SMC Title 17C) |
| Side Setback | Confirm with Vancouver Planning (VMC 20.810.040) | Confirm with Spokane Planning (SMC Title 17C) |
| Front Setback | Confirm with Vancouver Planning (VMC 20.810.040) | Confirm with Spokane Planning (SMC Title 17C) |
Permits & Timeline
| Detail | Vancouver, WA | Spokane, WA |
|---|
| Permit Timeline | 45-65 days | 50-75 days |
| Permit Fees | $1,900-$3,200 | $2,000-$3,500 |
| Impact Fees | $700-$1,300 | $600-$1,200 |
| Pre-Approved Plans | Available | Limited availability |
Construction Costs
| Cost | Vancouver, WA | Spokane, WA |
|---|
| Avg Build Cost | $135,000-$270,000 | $110,000-$220,000 |
| Cost Per Sq Ft | $130-$260 | $110-$220 |
| Garage Conversion | $65,000-$155,000 | $50,000-$120,000 |
| Prefab ADU | $95,000-$220,000 | $80,000-$180,000 |
Rental Income Potential
| Rental | Vancouver, WA | Spokane, WA |
|---|
| 1BR Avg Rent | $1,250-$1,700/mo | $1,000-$1,450/mo |
| 2BR Avg Rent | $1,600-$2,300/mo | $1,300-$1,900/mo |
| Short-Term Rentals | Permitted with license | Allowed, but owner-occupancy is required when the lot is use |
| Est. ROI | 7-9% annual return | 8-12% annual return |
Which City Is Better for ADUs?
Vancouver scores 7/10 while Spokane scores 6/10 on our ADU-friendliness index.
Vancouver 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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