How Gilbert Handles Accessory Structures: A Practical Guide

Gilbert 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 Gilbert falls on the strict-to-permissive spectrum compared to other cities.

ADU Impact Fees

Gilbert charges development impact fees on new ADUs under ARS 9-463.05, but HB 2720 caps ADU impact fees in cities over 75,000 at no more than 50 percent of single-family detached rates in each category. Water and sewer capacity fees apply where a new meter is installed; shared utilities avoid those charges.

Key details: Fee Authority: ARS §9-463.05. ADU Cap: 50% of single-family rate. Typical Total: $4,000-$9,000. Permit Fee: $600-$1,800 typical.

Failure to pay impact fees before permit issuance prevents construction. Gilbert may file liens for unpaid fees. Building without paying impact fees through unpermitted construction triggers double fees plus civil penalties under the Land Development Code.

Gilbert is more permissive than most cities when it comes to adu impact fees. That said, there are still limits.

ADU Rental Restrictions

Gilbert permits long-term ADU rentals without registration or licensing. HB 2720 prohibits Gilbert from imposing minimum-lease terms longer than 30 days or banning ADU rentals. Short-term ADU rentals (under 30 days) require Gilbert vacation rental registration under ARS 9-500.39 and remittance of Transaction Privilege Tax.

Key details: Long-Term: No registration required. STR Statute: ARS §9-500.39. Min Lease Cap: 30 days max. STR Insurance: $500,000 minimum.

Unregistered STR operation in Gilbert carries civil penalties up to $1,000 per day under ARS 9-500.39 and the local Town Code. Unpaid Transaction Privilege Tax triggers Arizona Department of Revenue audit and collection. HOA CC&R violations are enforced through civil action and may include fines, liens, and injunctions.

The rules around adu rental restrictions in Gilbert lean permissive, but that does not mean anything goes.

ADU Permits

Gilbert processes ADU permits through Development Services. Arizona HB 2720 (signed May 2024, effective January 1, 2025) preempts most local ADU restrictions in cities over 75,000 residents and codifies ADU rules at ARS 9-461.18. Gilbert (population over 280,000) must allow at least one attached and one detached ADU per single-family lot by right.

Key details: State Law: ARS §9-461.18 (HB 2720). City Code: Gilbert LDC Chapter 5. Review Type: By right (no Use Permit). Max Side/Rear Setback: 5 ft. Review Time: 10-20 business days.

Building an ADU without permit triggers stop-work orders, double permit fees, and civil penalties under Gilbert's Land Development Code enforcement provisions. Continued violations face escalating daily fines and potential misdemeanor charges. Liens may be filed on the property to recover unpaid penalties and fees.

ADU Owner Occupancy

Gilbert previously required owner-occupancy as a condition of casita approval, but Arizona HB 2720 (ARS 9-461.18) preempts owner-occupancy requirements in cities over 75,000 population. Gilbert may no longer condition ADU permits on the owner residing on-site. HOA CC&Rs may still impose restrictions, subject to limits under ARS 33-1817.

Key details: Status: Preempted by HB 2720. Effective Date: January 1, 2025. HOA CC&Rs: Limited by ARS §33-1817. Rentable: Both units now.

No municipal enforcement of owner-occupancy after January 1, 2025. HOA enforcement of CC&R owner-occupancy clauses may continue but is subject to challenge under ARS 33-1817. HOA fines for CC&R violations vary by community, typically $25-$250 per violation with continuing daily escalation.

Gilbert is more permissive than most cities when it comes to adu owner occupancy. That said, there are still limits.

Shed Rules

Gilbert requires building permits for structures 200 sq ft or larger, or any structure with utilities. Smaller structures without utilities are permit-exempt. Buildings must meet prescribed setbacks per the Land Development Code.

Key details: Permit Threshold: 200 sq ft or utilities. Under 200 sq ft: Permit-exempt (setbacks apply). Screening: Required from neighbors. Contact: Development Services 480-503-6700.

Building without required permit: stop-work order and fines. Structures violating setbacks: zoning violation requiring relocation or removal.

Garage Conversions

Garage conversions to ADUs are permitted under HB 2720 with a building permit. Converted spaces must meet residential building codes. Gilbert previously required compatible design, which HB 2720 eliminated.

Key details: Status: Permitted under HB 2720. Permit: Building permit required. Design Match: No longer required (HB 2720). HOA: May still restrict.

Conversion without permit: stop-work order. Non-compliant habitable space: building code violation. HOAs may impose separate enforcement.

Carport Rules

Carport construction in Gilbert requires a building permit and must meet zoning setback and height requirements. Carports are classified as accessory structures under the Land Development Code.

Key details: Permit: Required. Setbacks: Per zoning district. Design: Compatible with home. HOA: May have additional standards.

Unpermitted carports are subject to code enforcement. Structures not meeting setback or design standards must be modified or removed.

ADU Rules

Gilbert permits ADUs up to 1,000 sq ft or 75% of the primary dwelling. State law HB 2720 requires a minimum 5-foot setback. ADU parking must be behind the main building and screened from the street.

Key details: Max Size: 1,000 sq ft or 75% of home. Setback: 5 ft minimum (HB 2720). Parking: Behind main building. State Preemption: HB 2720 casita law.

Unpermitted ADUs face code enforcement. ADUs exceeding size limits or not meeting setback requirements must be modified to comply.

Tiny Homes

Gilbert allows tiny homes as ADUs on permanent foundations, limited to 1,000 sq ft or 75% of the primary dwelling. Tiny homes on wheels are classified as RVs and cannot be permanent residences.

Key details: Max Size: 1,000 sq ft or 75% of home. Foundation: Permanent required for ADU. THOWs: Classified as RVs. State Law: HB 2720 applies.

Unpermitted tiny homes or THOWs used as permanent dwellings face code enforcement including orders to cease occupancy.

The Bottom Line

Compared to many U.S. cities, Gilbert gives residents more room on accessory structures. 3 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 Gilbert 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.