Casita and ADU guides
Updated October 9, 2026
Plain-language guides to building a casita (ADU) in the Phoenix area, written from the state law and the cities' own zoning codes.
- Arizona's ADU law, explainedWhat every city over 75,000 people has to allow since 2025: two ADUs, up to 1,000 sq ft, 5 ft setbacks.
- Casita and ADU rules in MesaCoverage and setbacks for every Mesa residential district.
- Casita and ADU rules in TempeLot coverage, easements, and what Tempe's planners confirmed.
- What a casita costs in ArizonaTypical Phoenix-area prices per square foot and what drives them.
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