Complete 2026 cost breakdown: construction, permits, financing, and expected rental ROI.
Building an ADU in Salt Lake City costs between $180,000-$350,000 for new construction, with per-square-foot costs averaging $300-$350. These figures include design, permitting, site preparation, and construction. The most affordable option is a garage conversion at $120,000-$200,000, while prefab/modular ADUs fall in between at $100,000-$180,000.
| Cost Category | Estimated Range |
|---|---|
| Architectural Plans | $3,000 – $15,000 |
| Permits & Fees | $2,000-$4,000 estimated |
| Impact Fees | Utility connection fees apply |
| Site Prep & Foundation | $10,000 – $35,000 |
| Framing & Structure | $15,000 – $45,000 |
| Plumbing | $8,000 – $20,000 |
| Electrical | $5,000 – $15,000 |
| HVAC | $3,000 – $8,000 |
| Interior Finishes | $15,000 – $40,000 |
Permit fees in Salt Lake City are $2,000-$4,000 estimated. The review timeline is 2-8 weeks for approval; 7-9 weeks for construction after permit issued; 3+ months total typical, with plan check taking approximately Included in 2-8 week timeline. Impact fees are Utility connection fees apply. Pre-approved plans: City offers ADU standard plans; ADU Handbook available.
| 1-Bedroom Rent | $1,200-$1,600/month |
| 2-Bedroom Rent | $1,600-$2,200/month |
| Annual Rental Income (est.) | $16,800/year |
| Payback Period (est.) | 15.8 years |
| Short-Term Rental | Restricted; long-term preferred |
| Overall ROI Estimate | 8-12 year payback; property value increase 20-35% |
A typical ADU in Salt Lake City generates approximately $16,800 per year in rental income based on average 1-bedroom rents. At an average construction cost of $265,000, the estimated payback period is 15.8 years — before accounting for property value appreciation, which typically adds 20-35% to home value.
1. Garage conversions save 40-60% vs new construction since the shell already exists. Average cost in Salt Lake City: $120,000-$200,000.
2. Prefab/modular ADUs offer predictable pricing and faster timelines. Average: $100,000-$180,000.
3. Pre-approved plans (City offers ADU standard plans; ADU Handbook available) can save $3,000-$10,000 in design costs and 2-3 months in review time.
4. State grants — California's CalHFA program offers up to $40K. Check your state for available programs.
5. Get multiple bids — ADU contractor pricing varies 20-40% for the same project. We recommend getting at least 3 quotes.
Compare prices from pre-screened ADU contractors in your area. Free, no-obligation estimates.
Find ADU Contractors →