Arizona ADU permit requirements
Last reviewed: June 20, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Arizona means pulling a building permit from the local authority that issues it. Arizona has a statewide ADU law that sets baseline standards local agencies must follow. ArchPermit tracks 16 source-cited requirements (11 required, the rest conditional) for this jurisdiction. These requirements were last reviewed June 20, 2026; confirm the exact forms and fees with the local permitting authority.
Arizona has a statewide ADU law. This baseline reflects that law plus the universal new-dwelling deliverables. Your local city or county still administers the permit and may add its own forms and fees, so confirm the exact checklist with them.
Arizona's A.R.S. § 9-461.18 (HB 2720, 2024) requires municipalities over 75,000 to allow one attached and one detached ADU where single-family dwellings are allowed. Arizona is home-rule with no mandatory statewide building/energy code; confirm the adopted code and ADU rules with your city/county.
- Adopted building code compliancerequired
The ADU must comply with the residential building code adopted by the local jurisdiction; confirm the edition with the AHJ.
source · reviewed 2026-06-20 - Building cross-sectionsrequired
Cross-sections through the structure showing ceiling heights, wall/roof assemblies, insulation, and fire/sound-rated assemblies where required.
source · reviewed 2026-06-20 - Egress & life-safetyrequired
Emergency escape and rescue openings (egress windows), smoke and carbon-monoxide alarms, and required exits per the adopted residential code.
source · reviewed 2026-06-20 - Energy code compliancerequired
Energy-code compliance documentation for the conditioned space (typically IECC / state energy code, e.g. CF1R-style forms), printed on or submitted with the plans.
source · reviewed 2026-06-20 - Exterior elevationsrequired
Elevations of each affected building face showing height, exterior materials, and openings; existing vs. proposed where exterior changes occur.
source · reviewed 2026-06-20 - Floor plansrequired
Dimensioned floor plans of the ADU (and affected areas of the primary dwelling) showing rooms, uses, door/window locations, egress, and fixture/equipment locations.
source · reviewed 2026-06-20 - Foundation planrequired
Foundation plan with footing/stem-wall sizes and details (or a cited site-specific design), per the adopted residential code.
source · reviewed 2026-06-20 - Framing / structural plansrequired
Floor, wall, and roof framing showing member sizes, spans, spacing, connections, and lateral bracing; structural calculations where the framing is non-conventional.
source · reviewed 2026-06-20 - Local zoning / setback compliancerequiredverify locally
Compliance with the local jurisdiction's zoning: permitted use, setbacks, height, lot coverage, and any ADU-specific standards. These are set locally. Confirm with the permitting agency.
source · reviewed 2026-06-20 - Mechanical / plumbing / electricalrequired
HVAC, plumbing fixtures and lines, and electrical (panels, circuits, outlets, lighting, smoke/CO alarms) for the new unit.
source · reviewed 2026-06-20 - Site / plot plan (to scale)required
Scaled site plan showing property lines, setbacks, existing structures, the proposed ADU footprint with dimensions to property lines, driveways/parking, and utility locations.
source · reviewed 2026-06-20 - No additional parking requiredconditional
Municipalities may not require added parking or fees-in-lieu for an ADU.
source · reviewed 2026-06-20 - No exterior design-matching requirementconditional
An ADU need not match the principal dwelling's exterior design, roof pitch, or materials.
source · reviewed 2026-06-20 - No owner-occupancy/relationship requirementconditional
No familial/marital/employment relationship between occupants may be required; separate long-term rental may not be prohibited.
source · reviewed 2026-06-20 - One attached + one detached ADU permittedconditionalverify locally
Municipalities >75,000 must allow ≥1 attached and ≥1 detached ADU as a permitted use where single-family is allowed.
source · reviewed 2026-06-20 - Rear/side setback ≤ 5 ftconditional
Covered municipalities may not require ADU rear/side setbacks greater than 5 ft.
source · reviewed 2026-06-20
Arizona ADU permit questions
- Do I need a permit to build an ADU in Arizona?
- Yes. An accessory dwelling unit (ADU) in Arizona requires a building permit, and Arizona has a statewide ADU law that sets baseline standards local agencies must follow. ArchPermit tracks 16 cited requirements for this jurisdiction (11 required, the rest conditional). Always confirm the exact forms, fees, and code edition with the local permitting authority that issues the permit.
- What does an ADU permit package require in Arizona?
- Core required items include: Adopted building code compliance; Building cross-sections; Egress & life-safety; Energy code compliance; Exterior elevations; Floor plans, plus 5 more. Each requirement links to its authoritative source, and nothing is permit-ready until an independent licensed professional reviews and seals it.