Tiny Homes in Idaho

Idaho stands out as one of the most tiny-home-friendly states in the Mountain West. It was the first state to fully adopt IRC Appendix Q and added its own Appendix V specifically for tiny homes. With Boise’s landmark decision to legalize THOWs as ADUs in July 2025, Blaine County’s NOAH+ standards, and rural counties that offer flexible placement, Idaho provides pathways for both foundation tiny homes and THOWs.

Where to Place a Tiny Home in Idaho

Boise is the clear leader. As of July 1, 2025, the city allows certified THOWs under 400 sq ft as ADUs in all residential zones where ADUs are permitted. THOWs must be NOAH+ or ANSI A119.5 certified and connected to permanent utilities. This followed a successful pilot program with LEAP Housing that was evaluated by Boise State University. The city also increased its maximum ADU size from 700 to 900 sq ft and lifted owner-occupancy requirements in many zones. Between 2019 and 2024, ADU construction in Boise increased 169%.

Blaine County has been a trailblazer for THOWs as ADUs. On lots between 2 and 5 acres, one NOAH+ certified THOW is a permitted use by right. The City of Hailey requires NOAH+ certification and offers up to $15,000 in workforce housing incentive grants for deed-restricted tiny homes or ADUs.

Gem County allows one THOW on parcels of one acre or more for up to one year, renewable with public screening. Moscow removed its six-month restriction on THOWs, allowing year-round hookups in mobile home parks. For the most affordable placement, eastern Idaho’s rural counties with large lot minimums are generally permissive for code-built tiny homes, and land can be purchased for $2,000 to $10,000 per acre.

Note: Meridian’s city code allows tiny homes and RVs to be parked in residential neighborhoods but bans living in them except in RV parks. This has been the subject of legal challenges through the Institute for Justice, so check the latest status before planning to locate there.

Idaho Tiny Home Builders

Tiny Idahomes in Emmett builds 50 to 60 custom THOWs per year and is RVIA certified, licensed, bonded, and insured. Models range from $40,000 to $78,000 and include tow-behind, 5th wheel, and toy hauler configurations. Financing is available through RV lenders since all homes are classified as RVs. They deliver nationwide.

Snake River Tiny Homes in Rexburg is a certified Women-Owned Small Business and green builder offering RVIA and NOAH+ certified park models and THOWs from $30,000 to $130,000. They use ductless HVAC, energy-efficient appliances, and recycled insulation. They serve Idaho Falls, Twin Falls, and Rexburg and ship nationwide.

Bigwood Tiny Homes in Hailey specializes in high-performance THOWs and ADUs built for mountain conditions. All homes are NOAH certified and inspected to ANSI+ standards. Founded in 2020 as a response to the local housing crisis, they offer the Alpenglow and Ruby models plus fully custom builds.

Southern Idaho Tiny Homes in Twin Falls has over 25 years of building experience and offers park model tiny homes at $129,000 for 396 sq ft models with heavy snow load roofs rated for 125 lbs per sq ft. Homes come titled and VIN’d as RVs. They build custom and ship across the US.

Hybrid Construction LLC in Spirit Lake follows IRC Appendix Q and holds certifications from the Tiny Home Industry Association (THIA). They build foundation tiny homes and ADUs in northern Idaho.

Key Regulations to Know

Idaho defines tiny homes under Appendix Q as dwellings of 400 sq ft or less on a permanent foundation, with a minimum of 150 sq ft. The 2020 Idaho Residential Code (based on the 2018 IRC) is the baseline statewide code. Loft requirements include a minimum of 35 sq ft, at least 30 inches above the main floor, and emergency egress via skylight or roof window.

THOWs are classified as recreational vehicles by the Idaho Transportation Department. Registration is handled through county assessor motor vehicle offices as travel trailers or camp trailers. RV fees are $8.50 for the first $1,000 of market value plus $5.00 per additional $1,000. RVIA certification is recommended as it simplifies DMV registration, insurance, and RV park acceptance.

House Bill 166 (2023) prohibits HOAs from banning attached ADUs on owner-occupied properties statewide. The law covers internal conversions like basement apartments, attic units, and garage conversions. Detached ADU rules still vary by jurisdiction. Owner-occupancy of either the primary home or ADU for at least six months per year is generally required.

Building permits are required from either local jurisdictions or the Idaho Division of Building Safety (which oversees counties without local building departments). Contact the Division at (208) 334-3950 or through the Idaho Division of Occupational and Professional Licenses website.