Arizona now has significant state-level accessory-dwelling-unit protections, while also drawing clear legal lines between factory-built buildings, manufactured homes and recreational vehicles such as park trailers. The exact city, town or county still controls the parcel-level zoning and permit path.
“Tiny house” is a lifestyle description. Regulators care about the legal building or vehicle classification.
Local zoning and building approval still control the parcel. Arizona state law now limits how counties regulate ADUs on lots where single-family dwellings are allowed, and a separate statute imposes similar requirements on municipalities above the statutory population threshold.
A.R.S. § 11-810.01 requires counties to allow at least one attached and one detached ADU as permitted uses on lots where a single-family dwelling is allowed, subject to the statute and its exceptions. A.R.S. § 9-461.18 establishes a related framework for municipalities with populations over 75,000.
Arizona separately defines factory-built buildings and HUD-code manufactured homes. Factory-built buildings exclude manufactured homes and recreational vehicles, so an off-site-built dwelling should be matched to its actual state classification before zoning or installation assumptions are made.
Arizona law defines a park trailer of roughly 320–400 square feet as a recreational vehicle and describes RVs as providing temporary living quarters for recreational, camping or travel use. That classification is different from a manufactured or factory-built dwelling even when the unit looks residential.
These pages use current city/county sources and deliberately separate permanent dwellings from THOW/community pathways.
Community acceptance does not replace zoning, building, utility or other government approvals. Confirm both the community rules and the legal pathway for the specific unit.
This page is research and planning information, not legal advice or a permit determination. Rules can change and local officials determine how they apply to a specific parcel and project.