Free Tiny House Zoning Finder

Tiny houses on permanent foundations are regulated as residential dwellings under local building codes. Many jurisdictions allow them through Appendix Q standards (120-400 sq ft). Tiny houses on wheels (THOWs) are classified as recreational vehicles or mobile homes, subject to more restrictive zoning that typically limits permanent residential use to RV parks or designated communities.

ADU regulations provide one of the clearest legal pathways for tiny houses. An ADU is a secondary dwelling on a property with an existing primary residence. States like California mandate ADU allowance statewide, while others leave it to local jurisdictions. ADU laws typically specify maximum sizes (400-1,200 sq ft), setback requirements, parking rules, and owner-occupancy requirements.

Appendix Q of the International Residential Code establishes building standards specifically for tiny houses 120-400 square feet on permanent foundations. It provides modified requirements for ceiling heights (6'8" in lofts vs. standard 7'), stairs, ladders, lofts, and emergency egress. Local jurisdictions must adopt Appendix Q for it to apply in their area. States like Oregon have statewide adoption, while others vary by county.

Requirements vary by jurisdiction but typically include: zoning verification that your parcel allows residential or ADU use, building permits with approved construction plans, septic or sewer approval from health departments, well or water connection permits, electrical and plumbing inspections during construction, final occupancy certificate after passing all inspections. THOWs may require RVIA or NOAH certification instead of traditional building permits.

Permanent occupancy of THOWs depends entirely on local zoning ordinances. Most jurisdictions classify them as RVs, prohibiting permanent residential use outside designated RV parks. Some progressive jurisdictions are creating THOW-specific ordinances allowing them as ADUs or in special zones. Always verify local zoning allows permanent THOW occupancy and that utilities can be legally connected before purchasing land.

California offers the strongest statewide support with mandatory ADU allowance and Appendix AQ adoption. Oregon has statewide Appendix Q and urban ADU requirements. Utah prohibits minimum size requirements below 300 sq ft statewide. Texas, North Carolina, Colorado, and Washington offer growing support through local jurisdictions. Rural areas in most states provide more flexibility but may lack infrastructure support.