With its mountain scenery, friendly small towns, and wide open spaces, Idaho is a favorite for those seeking a simpler lifestyle and affordable land. But Idaho’s approach to tiny home living is a mix of old-school codes and new opportunities. If you’re interested in building, buying, or parking a tiny home—on wheels or on a foundation—here’s the essential guide to Idaho tiny home laws for 2025.
Are Tiny Homes Legal in Idaho?
Idaho does not have a single statewide law for tiny homes. Instead, each city and county sets its own rules for zoning, building codes, and occupancy. Some places are making it easier for tiny houses—especially in rural areas—while cities often have stricter codes. The good news: Idaho adopted Appendix Q of the International Residential Code (IRC), which makes it much simpler to legally build tiny homes under 400 sq. ft. in many places.
Quick Picks: Best Idaho Cities and Counties for Tiny Homes
- Boise: The state capital allows Accessory Dwelling Units (ADUs) and is considering more options for backyard cottages and tiny homes on foundations. (City code)
- Ada County: Home to Boise and Meridian, Ada County is open to ADUs and has updated some rules for small homes. (County info)
- Valley County (McCall area): Known for flexible codes and several rural tiny home communities.
- Bonner & Boundary Counties (North Idaho): Popular for off-grid and rural tiny home living with fewer restrictions, especially on large parcels.
- Rural Areas & Small Towns: Many rural Idaho counties are open to owner-built cabins, small homes, or THOWs (tiny homes on wheels), but always check with your county before building or moving in.
Local codes, zoning, and enforcement vary, so always contact your city or county planning office first.
Buyer’s Guide: Key Issues for Tiny Homes in Idaho
- Type of Tiny Home: Is your tiny home built on a foundation (permanent), or is it a tiny home on wheels (THOW)? Idaho law and local codes treat these differently.
- Building Codes: Idaho uses the International Residential Code (IRC) with Appendix Q, which allows for tiny homes as small as 170 sq. ft. in many counties and cities. Most rural areas may have even fewer requirements.
- Zoning Laws: You must build or park your tiny home in a zone that allows residential, manufactured, or accessory dwellings. Rural and agricultural land is often most flexible.
- Minimum Square Footage: No state minimum—many areas allow homes under 400 sq. ft. with Appendix Q. Cities may set their own minimums (often 170–400 sq. ft.).
- Utilities: Permanent homes must have approved water, septic or sewer, and electrical service. Off-grid living is allowed in many rural zones if you meet health and sanitation rules.
- Permits & Inspections: All legal tiny homes must be permitted, pass inspections, and get a certificate of occupancy.
- HOA/Community Rules: Homeowners associations and some planned communities can ban tiny homes, RVs, or THOWs, even if the county allows them.
Detailed Reviews: Idaho Tiny Home Laws by Category
Tiny Homes on Foundations
These are the most straightforward to legalize in Idaho. Appendix Q of the IRC (adopted statewide) allows site-built tiny homes as small as 170 sq. ft., with safety and design exceptions for small spaces. Many rural counties allow even smaller cabins with fewer inspections.
- Must meet IRC/Appendix Q code for tiny homes
- Minimum size: 170 sq. ft. (cities may require more)
- Utilities, permits, and inspections required
- Allowed in most residential, rural, and ag zones
Final Verdict: The best path for legal, full-time tiny home living in Idaho—especially on your own land.
Tiny Homes on Wheels (THOWs)
Idaho generally treats THOWs as RVs or park models. Full-time living in a THOW is legal only in RV parks, tiny home communities, or, in some rural counties, on private land (with local approval).
- Must be certified as an RV or park model in most areas
- Can be lived in full-time in RV parks, some rural parcels, or permitted tiny home communities
- Most cities prohibit THOWs as backyard dwellings or permanent homes
- Sanitation, water, and power requirements apply
Final Verdict: Great for seasonal, mobile, or rural living, but less accepted in Idaho cities.
Accessory Dwelling Units (ADUs)
Idaho’s growing cities, especially Boise, now allow ADUs or backyard cottages on many single-family lots. ADUs are a popular way to add legal tiny housing for family or rental income.
- Must have a main house on the lot
- Minimum size: 170–400 sq. ft. typical
- Permits, inspections, and utilities required
- Check for setback and lot size requirements
Final Verdict: The most city-friendly option for tiny homes in Idaho, especially for rentals or multigenerational living.
Comparison Table: Idaho Tiny Home Options
| Type | Where Legal? | Minimum Size | Key Requirements |
|---|---|---|---|
| Tiny Home on Foundation | Boise, Ada County, Valley, Bonner, most rural | 170 sq. ft. (Appendix Q); cities may require more | Meets code, permits, full utilities |
| Tiny Home on Wheels (THOW) | RV parks, tiny home villages, some rural land | 100–400 sq. ft. typical | Certified as RV/park model, zoning must allow |
| Accessory Dwelling Unit (ADU) | Boise, many cities, rural towns | 170–400 sq. ft. | Main house required, permits, utilities |
Frequently Asked Questions (FAQ)
What is the minimum legal size for a tiny home in Idaho?
With Appendix Q, Idaho allows homes as small as 170 sq. ft. Many cities and rural counties accept homes under 400 sq. ft. with proper permits and code compliance.
Can I live full-time in a tiny home on wheels in Idaho?
Yes, if you’re in an RV park, permitted tiny home village, or, in some rural counties, on private land with approval. Most cities do not allow full-time THOW living on standard residential lots.
Are off-grid tiny homes allowed in Idaho?
Yes, especially in rural areas—if you meet water, septic, and health standards. Cities typically require full utility hookups.
Can I put a tiny home in my backyard in Idaho?
If your city or county allows ADUs, yes—subject to setback, size, and utility requirements. Always check local codes.
Are shipping container homes legal in Idaho?
In many rural areas, yes—if built to code and with all required permits. Cities may have stricter standards and design requirements.
Conclusion
Idaho is an increasingly tiny home-friendly state, especially thanks to its adoption of Appendix Q. Rural areas and smaller towns are the most welcoming, while cities are opening up slowly through ADU reforms and updated building codes. Always check with your local planning office, review zoning and HOA rules, and get every required permit before building or moving in. With a bit of homework, you can enjoy small-space living and the Idaho outdoors for years to come.
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