Idaho Falls, ID Accessory Structures: Tiny Homes (2026)

Idaho Falls does not have a standalone tiny-home ordinance; how a tiny home is regulated depends on its form. A small permanent house built on a foundation is treated as a single-family dwelling and must meet Title 11 zoning standards for its zone plus adopted building codes, including eastern Idaho snow and wind loads. A small detached secondary dwelling in the backyard is treated as an accessory dwelling unit (ADU) under the city's zoning ordinance. ADUs are allowed in the RP and R1 low-density zones and the RMH medium-density zone, are capped at 750 square feet, and must meet ADU standards: owner-occupancy of one unit on the lot recorded as a deed restriction with the Bonneville County Recorder, one additional off-street parking space, and a twelve-foot (12') rear setback for detached units (less when adjacent to a 16-foot alley). Critically, recreational vehicles are prohibited for use as an accessory dwelling unit, so a tiny home on wheels titled as an RV cannot serve as a permanent residence. Anyone planning a tiny home should confirm with Community Development Services whether it will be permitted as a primary dwelling or an ADU, since that determines the size cap, parking, occupancy, and permit path.