How Tempe Handles Accessory Structures: A Practical Guide

Tempe maintains 119 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 Tempe falls on the strict-to-permissive spectrum compared to other cities.

ADU Impact Fees

Tempe does not impose a dedicated ADU impact fee. Standard building, plumbing, mechanical, and electrical permit fees through Tempe Community Development apply based on construction valuation. Water and sewer development fees apply only when a new utility connection is installed. Arizona HB 2720 (ARS 9-461.18) limits fees that would effectively prohibit ADU construction.

Key details: Dedicated ADU Impact Fee: None. Fee Authority: ARS 9-463.05. State Cap: ARS 9-461.18 limits punitive fees. Utility Fees: Only if new meter or connection. Permit Fee Basis: Construction valuation.

Failure to pay required permit and connection fees blocks issuance of the building permit and prevents lawful construction. Bypassing the fee process by building without a permit triggers double-fee assessment, civil penalties, and code enforcement action. Unauthorized utility tap-ins discovered later can result in disconnection, back-billing, and lien recording.

If you are coming from a city with tighter rules, you will find Tempe gives residents more flexibility on adu impact fees.

ADU Rental Restrictions

Tempe permits long-term ADU rentals without a city license. Short-term rentals (under 30 days) require an Arizona Department of Revenue transaction privilege tax license and a Tempe Short-Term Rental permit under City Code regulations adopted consistent with ARS 9-500.39. HB 2720 prohibits ADU-specific rental bans. ASU-area demand makes rentals common but Tempe enforces strict STR registration, local-contact, and notice rules.

Key details: Long-Term: No city registration required. STR State Statute: ARS 9-500.39 (SB 1350 / HB 2672). Local Contact: 1-hour response required. Neighbor Notice: Required before operating. TPT License: Required for STR.

Operating an STR without a Tempe permit or Arizona TPT license triggers civil penalties, back-tax assessment by the Department of Revenue, and permit revocation. ARS 9-500.39 authorizes Tempe to suspend or revoke the STR permit for repeated nuisance, noise, or occupancy violations. HOA STR restrictions are enforceable through CC&R fines and civil action. Failure to provide the one-hour-response local contact is an independent violation.

ADU Permits

Tempe permits accessory dwelling units by right on lots zoned for single-family use under Arizona Revised Statutes section 9-461.18, enacted by HB 2720 in 2024. Tempe (population approximately 185,000) is well over the 75,000 threshold that triggers the state by-right mandate. Tempe's Zoning and Development Code was amended to comply, allowing at least one attached and one detached ADU per single-family lot. Building permits issue through Tempe Community Development.

Key details: State Law: ARS 9-461.18 (HB 2720). City Code: Tempe ZDC + City Code Ch. 8. Units Allowed: 1 attached + 1 detached by right. Max Side/Rear Setback: 5 ft (state cap). Population Threshold: Tempe ~185k qualifies (over 75k).

Constructing or occupying an ADU without permits violates Tempe City Code Chapter 8 and the Zoning and Development Code, triggering stop-work orders, double permit fees on legalization, and civil penalties through Tempe Code Compliance. Continued violations face escalating daily fines and potential misdemeanor charges. Liens may attach to non-compliant properties. Lack of a final certificate of occupancy prevents lawful habitation and complicates future sale.

The rules around adu permits in Tempe lean permissive, but that does not mean anything goes.

ADU Owner Occupancy

Tempe does not require owner occupancy for ADUs. Arizona HB 2720 (ARS 9-461.18) prohibits cities over 75,000 population from conditioning ADU permits or use on owner occupancy. Both the primary residence and the ADU may be rented to separate tenants. HOA CC&Rs in Tempe's smaller HOA communities (The Lakes, Warner Ranch, Circle G Ranches) may still impose occupancy restrictions subject to ARS 33-1817.

Key details: Status: Not required (HB 2720 preempts). State Statute: ARS 9-461.18. Both Units Rentable: Yes. HOA Layer: Light but present (The Lakes, Warner Ranch). HOA Statute: ARS 33-1817.

No city enforcement of owner-occupancy. HOA enforcement of CC&R owner-occupancy provisions continues but is subject to legal challenge under ARS 33-1817. HOA fines typically range from $25 to $250 per violation under the community's adopted enforcement schedule, with escalation provisions and the possibility of attorney fee awards in covenant litigation.

The rules around adu owner occupancy in Tempe lean permissive, but that does not mean anything goes.

ADU Rules

Tempe permits Accessory Dwelling Units (ADUs) in residential zones following a 2022 ordinance update. ADUs can be detached, attached, or converted from existing structures. They must meet size, setback, and design standards but do not require additional parking.

Key details: Max Size: 75% of primary home or 1,000 sq ft. Setbacks: 5 feet from side and rear lines. Parking: No additional parking required. STR Use: Not permitted for rentals under 30 days. Design: Must match primary dwelling style.

Building an ADU without permits may result in stop-work orders and fines. Non-compliant ADUs must be brought into compliance or removed. Using an ADU as an STR in violation of the rules may result in penalties.

Garage Conversions

Garage conversions in Tempe require a building permit and must comply with zoning standards including parking requirements. Converting a garage to living space may require providing replacement off-street parking.

Key details: Permit: Required for all garage conversions. Parking: Must maintain minimum off-street spaces. Building Code: Must meet habitation standards. ADU Option: May convert under ADU regulations.

Unpermitted garage conversions may result in code enforcement action. Owners may be required to restore the garage or obtain retroactive permits with any needed upgrades to meet code.

Shed Rules

Tempe allows sheds and other accessory structures in residential zones. Small sheds under 200 square feet typically do not require a building permit but must comply with setback and height requirements under the zoning code.

Key details: Permit Exempt: Under 200 sq ft, one story. Setbacks: 3–5 feet from property lines. Lot Coverage: Counts toward maximum. Habitation: Not permitted.

Sheds violating setbacks or lot coverage limits may receive code enforcement notices requiring relocation or removal. Sheds used for habitation are subject to immediate enforcement action.

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

Tiny Homes

Tiny homes on permanent foundations may be permitted in Tempe as ADUs under the city's Zoning and Development Code. Tempe allows both attached and detached ADUs on single-family lots. Tiny homes on wheels are classified as recreational vehicles and cannot serve as permanent residences. Arizona HB 2720 (2024) expanded ADU rights statewide, and Tempe updated its ADU ordinance accordingly.

Key details: On Foundation: Permitted as ADU, must meet IRC standards. On Wheels: Classified as RV, no permanent residence allowed. ADUs Allowed: 1 attached + 1 detached per single-family lot. Height: Regulated by zoning district standards. State Law: AZ HB 2720 expanded ADU rights.

Using a tiny home on wheels as a permanent residence violates zoning code. Building an ADU without permits results in code enforcement action.

Carport Rules

Carports in Tempe are regulated under the Zoning and Development Code and building code (Chapter 8). A building permit is required for carport construction. Carports must comply with setback requirements of the applicable zoning district. Accessory structures like ramadas and small sheds are limited to 200 square feet and 8 feet in height before being classified as accessory buildings subject to additional standards.

Key details: Permit Required: Yes, building permit required. Small Structure: Up to 200 sq ft / 8 ft tall = accessory structure. Larger Structure: Over 200 sq ft or 8 ft = accessory building, additional standards. Lot Coverage: Counts toward maximum lot coverage. Building Code: International Building Code as adopted.

Constructing a carport without a permit or outside setback limits may result in code enforcement action, fines, and required removal or modification.

The Bottom Line

Compared to many U.S. cities, Tempe gives residents more room on accessory structures. 4 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.

This guide is based on Tempe's current municipal code. Local rules can and do change, so check the individual ordinance pages for the latest details, penalties, and FAQs.