Caldwell, ID Accessory Structures: Tiny Homes (2026)

Caldwell City Code Section 10-01-10 defines 'Dwelling - Single Family (Detached)' as a one-family dwelling not attached to any other principal dwelling, and the same definition expressly folds in detached tiny homes that comply with the International Residential Code, alongside detached cottage-type housing. That single sentence is the operative local rule for tiny homes in Caldwell: rather than creating a separate tiny-home permit track, the code simply recognizes a code-compliant tiny house as a species of detached single-family dwelling. That classification carries real consequences. Because a tiny home is a single-family dwelling and not an accessory structure in this framework, it is treated as the principal residence on the lot for zoning purposes, meaning it must meet the applicable residential district's own use, height, and lot-coverage rules rather than any lighter accessory-building standard.

The same definition also notes that a detached single-family dwelling may separately include an attached or detached Accessory Dwelling Unit under Chapter 10, Article 12, a distinct use from a stand-alone tiny home serving as the primary residence. Idaho's building code framework, adopted through the state's I-code chapters, governs the construction standards a tiny home must meet to qualify as IRC-compliant; Caldwell's zoning code does not independently amend those construction requirements, it only decides how the resulting structure is classified once built. Because the definition does not carve out a minimum square footage or a district-by-district prohibition specific to tiny homes, any restriction ultimately traces back to the ordinary dimensional and use standards that apply to detached single-family dwellings generally in whichever residential district the home is sited.