How Phoenix Handles Accessory Structures: A Practical Guide

Phoenix maintains 251 local ordinances across all categories, and 9 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where Phoenix falls on the strict-to-permissive spectrum compared to other cities.

Shed Rules

In Phoenix, one-story detached tool and storage sheds, playhouses and similar uses do not require a building permit if their aggregate floor area does not exceed 200 square feet, per Phoenix Building Construction Code Section 105.2.1. Sheds must still meet zoning setbacks of at least 3 feet from a side or rear property line under Zoning Ordinance Section 706.B.

Key details: Permit-exempt size: 200 sq ft or less, one story. Side/rear setback: 3 ft minimum. Front yard: Not permitted (use permit required between dwelling and front line). Max height: 8 ft within 5 ft of street side; 15 ft elsewhere in yard. Code Section: PBCC 105.2.1(1); Zoning Ordinance 706.B.

Erecting a shed that exceeds the 200 sq ft permit-exemption without a permit, or that violates zoning setbacks/height limits, is a code violation. The Planning and Development Department may require a permit be obtained or the structure relocated or removed; continued non-compliance is enforced through notices of violation and civil penalties under the Phoenix City Code.

Phoenix is more permissive than most cities when it comes to shed rules. That said, there are still limits.

ADU Owner Occupancy

Phoenix had a long-standing owner-occupancy requirement for casitas under PZC Section 608, but Arizona HB 2928 (2025) preempts this restriction for cities over 75,000 population. Phoenix cannot now require owner-occupancy as a condition of ADU permits or use.

Key details: Status: Preempted by HB 2928 (2025). Pre-2025 Rule: Was required under §608. HOA CC&Rs: Subject to ARS §33-1817. Rentable: Both units now.

No city enforcement of owner-occupancy after 2025. HOA enforcement of owner-occupancy CC&Rs may continue but is subject to challenge under ARS 33-1817. HOA fines for CC&R violations vary by community but typically range $25-$250 per violation.

If you are coming from a city with tighter rules, you will find Phoenix gives residents more flexibility on adu owner occupancy.

ADU Permits

Phoenix processes ADU permits through Planning and Development under PZC Section 608 (Casita Ordinance) and 2024 Phoenix ADU updates. Arizona HB 2928 (effective 2025) preempts local restrictions in cities over 75,000 residents, requiring ministerial approval for ADUs meeting state standards.

Key details: State Law: AZ HB 2928 (2025). City Code: Phoenix PZC Section 608. Max Size: 75% primary or 1,000 sq ft. Review Type: Ministerial (no hearing). Review Time: 10-20 business days.

Building an ADU without permit results in stop-work orders, double permit fees, and civil penalties up to $2,500 per violation under PZC enforcement. Continued violations face daily fines and potential criminal misdemeanor charges. Liens may be filed on the property.

ADU Impact Fees

Phoenix charges modest development impact fees on ADUs under Arizona Revised Statutes Section 9-463.05. HB 2928 caps ADU impact fees in cities over 75,000 at 50 percent of single-family rates. Phoenix water and wastewater capacity charges apply where new meters are installed.

Key details: Fee Authority: ARS §9-463.05. ADU Cap: 50% of single-family rate. Typical Total: $4,000-$8,000. Permit Fee: $500-$1,500 typical.

Failure to pay impact fees before permit issuance prevents construction. Phoenix may file liens for unpaid fees. Bypassing impact fee assessment through unpermitted construction triggers double fees plus civil penalties under PZC enforcement.

The rules around adu impact fees in Phoenix lean permissive, but that does not mean anything goes.

ADU Rental Restrictions

Phoenix permits long-term ADU rentals without registration or licensing. Short-term ADU rentals (under 30 days) require a state vacation rental license under ARS 9-500.39 and Phoenix STR registration. HB 2928 (2025) prohibits Phoenix from banning ADU rentals or imposing minimum-lease terms.

Key details: Long-Term: No registration required. STR Statute: ARS §9-500.39. TPT Rate: 12.57% combined. Local Contact: 1-hour response required.

Unregistered STR operation in Phoenix carries fines up to $1,000 per day under PCC Section 10-198. Unpaid TPT triggers Arizona Department of Revenue audit and collection. HOA STR restrictions enforceable through civil action and CC&R remedies including fines and injunctions.

Phoenix is more permissive than most cities when it comes to adu rental restrictions. That said, there are still limits.

Carport Rules

Phoenix Zoning Ordinance Sections 701 and 706 regulate carports as accessory structures. Open carports may project into required front yards up to 5 feet, into side yards to within 3 feet of the lot line, and into rear yards to within 3 feet of a common rear lot line. Detached ADUs may include an integrated carport.

Key details: Zoning Sections: §701, §706. Front Yard Projection: Up to 5 ft into required setback. Side Yard Minimum: 3 ft from lot line. Rear Yard Minimum: 3 ft from common rear lot line. ADU Integration: Carport area excluded from ADU floor area.

Unpermitted carports: stop-work orders, required removal or retroactive permitting with penalty fees. Fines $200 to $1,000.

Tiny Homes

Phoenix allows accessory dwelling units (ADUs) under Zoning Ordinance Section 706, which can function as tiny homes. Up to 2 ADUs are permitted per single-family lot (one attached, one detached). ADUs are capped at 75% of the primary dwelling's floor area, with a 1,000 sq ft maximum on lots up to 10,000 sq ft. HOAs may impose additional restrictions.

Key details: Zoning Section: Phoenix Zoning Ordinance §706. Max ADUs: 2 per lot (1 attached + 1 detached). Size Limit (≤10k sq ft lot): 1,000 sq ft max. Size Limit (>10k sq ft lot): Lesser of 3,000 sq ft or 10% of lot. Height (in setback): 15 ft max for detached ADU.

Unpermitted dwellings: removal or retroactive permitting. Zoning violations: fines and required relocation. Occupancy without certificate: prohibited.

ADU Rules

Phoenix permits up to two accessory dwelling units (one attached, one detached) on a single-family detached lot, with a third allowed on lots of one acre or more when one ADU is affordable housing. A detached ADU may sit as close as 5 feet from a street side property line and 3 feet from an interior side or rear line under Zoning Ordinance Section 706.A.

Key details: ADUs per lot: 2 (1 attached + 1 detached); 3rd on 1-acre affordable lots. Detached ADU setback: 5 ft street side / 3 ft interior side or rear. Max height in required yard: 15 ft (use permit for more). Max size: 75% of primary dwelling, max 1,000 sq ft (small lots). Code Section: Zoning Ordinance Sec. 706.A; A.R.S. 9-461.18.

Constructing an ADU without required permits or outside the Section 706.A standards is a zoning and building-code violation enforced by the Planning and Development Department and Neighborhood Services. The city may issue a stop-work order or notice of violation and require correction; uncorrected violations can lead to civil code-enforcement action under the Phoenix City Code.

Phoenix is more permissive than most cities when it comes to adu rules. That said, there are still limits.

Garage Conversions

Phoenix allows converting an existing garage or carport into an Accessory Dwelling Unit, but the conversion must establish new equivalent off-street parking elsewhere on the lot in dustproof condition, and that replacement parking may not be placed in the front-yard setback. A converted garage ADU is regulated under Zoning Ordinance Section 706.A and requires building permits.

Key details: Garage conversion to ADU: Allowed (attached or detached). Replacement parking: Required, dustproof, not in front setback. ADU size cap: 75% of primary dwelling, max 1,000 sq ft (small lots). Permit: Construction permit + 2 sets of plans. Code Section: Zoning Ordinance 706.A; A.R.S. 9-461.18.

Converting a garage to living space without permits, or failing to provide compliant replacement parking, is a zoning and building-code violation. The Planning and Development Department may deny final approval, issue a notice of violation, and require permits or restoration of parking; persistent violations are subject to code-enforcement penalties under the Phoenix City Code.

The Bottom Line

Compared to many U.S. cities, Phoenix gives residents more room on accessory structures. 5 of the 9 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.

Keep in mind that Phoenix can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.