Treasure Valley · By County

ADU rules change at every county line

We build accessory dwelling units across the whole Treasure Valley. Impact fees, owner-occupancy rules, size caps, and rent ceilings all shift county to county — here's the map.

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Treasure Valley

ADU builder for Idaho's Treasure Valley — Boise, Meridian, Nampa, Caldwell, Eagle, Kuna, Star, and Garden City. How ADU rules, impact fees, and rent change between Ada and Canyon county, and which county pencils out best.

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By county

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Each county page rolls up the cities we serve, the impact-fee and zoning differences, and the fastest path to a permitted ADU.

Ada County

Seat: Boise

ADU builder for Ada County, Idaho — Boise, Meridian, Eagle, Kuna, Star, and Garden City. How ADU rules, ACHD impact fees, and rent ceilings vary city to city, and which pre-approved plan fits.

Explore Ada County

Canyon County

Seat: Caldwell

ADU builder for Canyon County, Idaho — Nampa, Caldwell, Middleton, and Parma. How ADU size caps, highway-district fees, and owner-occupancy rules differ city to city in Idaho's second-largest county, and which plan fits.

Explore Canyon County

Gem County

Seat: Emmett

ADU builder for Gem County, Idaho — Emmett and the Emmett Valley up Highway 16. How city-of-Emmett ADU rules differ from unincorporated Gem County's 5-acre secondary-dwelling code, and which pre-approved plan fits.

Explore Gem County

Payette County

Seat: Payette

ADU builder for Payette County, Idaho — Payette and Fruitland on the Oregon border. How ADU rules differ in small cities under 10,000 population, why SB 1354 doesn't auto-apply here, and what a backyard unit costs.

Explore Payette County

Elmore County

Seat: Mountain Home

ADU builder for Elmore County, Idaho — Mountain Home and Glenns Ferry. How a backyard ADU pencils as a rental near Mountain Home Air Force Base, what the local permit path looks like, and which pre-approved plan fits.

Explore Elmore County

Owyhee County

Seat: Murphy

ADU builder for Owyhee County, Idaho — Homedale and the rural Snake River communities. Lower land cost, farm-stay and multigenerational ADUs, and how rural county zoning differs from the Treasure Valley cities.

Explore Owyhee County

Not sure which rules apply to your lot?

Send us your address. We'll confirm the county, the city code, the impact fees, and which pre-approved plan fits — free, within 24 hours.

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