Showing ordinances that apply to Ajo, AZ
Ajo is an unincorporated community (population 3,039) in Pima County, Arizona. Because Ajo is not an incorporated city, it does not have its own municipal code. Instead, Pima County ordinances apply directly to properties here. The tiny homes rules below are the ones that govern your area.
Pima County permits tiny homes as accessory dwelling units under the 2024 Zoning Code update for unincorporated areas. Tiny homes on wheels are classified as recreational vehicles and cannot serve as permanent dwellings. Site-built or modular tiny homes on foundations must meet IRC building standards and obtain standard building permits through Pima County Development Services.
Pima County Development Services regulates tiny homes through the county zoning code and building code (based on 2018 IRC). A tiny home on a permanent foundation is treated as a standard dwelling and must comply with minimum habitable space requirements, setbacks, and utility connections. Tiny homes on wheels (THOWs) are classified as RVs under Arizona law and may not be used as primary residences in residential zones. The county requires a building permit for any structure intended for habitation. Minimum lot sizes in unincorporated Pima County vary by zone (CR-1 requires 36,000 sq ft minimum, CR-3 allows 1-acre lots). Accessory dwelling units including tiny homes must connect to approved water and wastewater systems or obtain ADEQ permits for private wells and septic. Contact Pima County Development Services at 520-724-9000 for permit requirements.
Building or occupying a tiny home without permits is a code violation subject to notice of violation and fines. Unpermitted structures may face stop-work orders and mandatory removal. Using a THOW as a permanent residence violates zoning code and may result in daily fines until corrected.
See how Ajo's tiny homes rules stack up against other locations.
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