ADU Cost in Jerome, Idaho
What it really costs to build an ADU in Jerome — by type, with Jerome-specific permit fees, rent, and ROI. Straight from local ADU builders.
Quick Answer
An ADU in Jerome, Idaho typically costs $80,000 – $150,000 for a garage conversion, $150,000 – $350,000 for a detached new build, and $150,000 – $280,000 all-in for a pre-fab/modular unit (roughly $150 – $300 per square foot finished). Add permits and impact fees on top.
ADU Cost by Type in Jerome
| ADU Type | Typical Jerome Cost | Timeline | Best For |
|---|---|---|---|
| Garage Conversion | $80,000 – $150,000 | 2–4 months | Lowest cost; existing garage in good shape |
| Detached New Build | $150,000 – $350,000 | 4–8 months | Maximum size + design flexibility |
| Pre-Fab / Modular | $150,000 – $280,000 | 8–14 weeks on-site | Faster on-site; straightforward lots |
| Per square foot (finished) | $150 – $300 / sq ft | ||
Permits & Fees in Jerome
Special Use Permit fee + valuation-based building permits. As an over-10,000 city, Jerome is covered by SB 1354.
These are in addition to the construction cost above. We get exact fee quotes from the local office for your specific project during the Feasibility Check — see our full line-item cost breakdown + ROI calculator for how the numbers add up.
Rental Income & ROI in Jerome
A 1-bedroom ADU in Jerome typically rents for $850–$1,300/month long-term (estimate). At this rate, an ADU often offsets much or all of its financing payment within a few years, on top of the 20–30% property value increase ADUs typically deliver (per FHFA research).
Want the exact numbers for your property and goals? Our free eligibility check tells you your maximum ADU size, and the Feasibility Check gives you a good/better/best budget for Jerome.
More for Jerome Homeowners
ADU Rules in Jerome
Zoning authority, size limits, setbacks, and SB 1354 status for Jerome County.
Full Cost Breakdown
13-category line-item breakdown + interactive ROI calculator.
Am I Eligible?
Instant check: your max ADU size + which floor plans fit your lot.
Financing
HELOC, construction loan, cash-out refi — and Idaho lender options.
Get Your Real ADU Budget for Jerome
Start with a free 10-15 minute Readiness Call, then book a Feasibility Check for a detailed good/better/best budget tailored to your property.