Accessory Structures in Mesa, AZ (2026)
3 verified accessory structures rules for Mesa, Arizona, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Mesa allows one attached ADU and one detached ADU per lot in any Agricultural, Residential, Commercial and Mixed Use, or Downtown district where a Single Residence is permitted. There's no minimum lot size, but an ADU's interior habitable area can't exceed 75% of the primary residence's footprint or 1,000 square feet, whichever is smaller, under Mesa City Code § 11-31-3.
Mesa Accessory Dwelling Unit Zoning Rules
Some RestrictionsMesa City Code, Title 11, Chapter 31, § 11-31-3
A.Applicability.1.One (1) attached ADU and one (1) detached ADU are permitted per lot or parcel in any of the following zoning districts where a Single Residence is allowed: Agricultural, Residential, Commercial and Mixed Use, and Downtown....B.General Requirements.1.There are no minimum lot size requirements to establish an ADU.2.An ADU shall have a separate and independent entrance from the p...
Shed & Carport Rules
Mesa exempts small detached accessory structures, tool sheds, storage sheds, playhouses, from the building permit requirement when they serve a single-family, duplex, or similar residential occupancy and stay at or under 200 square feet, under Title 4, Chapter 1. The exemption doesn't apply on Desert Uplands land, in Historic Preservation Overlay Districts, or on landmark sites.
Mesa Storage Shed Permit Exemption (200 Sq Ft)
Some RestrictionsMesa City Code, Title 4, Chapter 1, § 4-1-4(B)(1)(a)
One- (1-) story detached accessory structures ancillary to R-3, R-4 and R-5 occupancies used as tool and storage sheds, playhouses, and similar uses, provided the floor area does not exceed two hundred (200) square feet (18.60m 2 ) and the property is not subject to the Desert Uplands Development Standards, is not located in a Historic Preservation Overlay District or on a site designated as a ...
Garage Conversions
Mesa lets homeowners convert an existing detached garage, carport, or accessory structure into an ADU without adding new setbacks, and doesn't require replacing the covered parking a converted garage or carport used to provide. Section 11-31-3(D)(2) and (G)(2) of the Zoning Ordinance govern the conversion.
Mesa Garage-to-ADU Conversion Rules
Some RestrictionsMesa City Code, Title 11, Chapter 31, § 11-31-3(D)(2), (G)
2.Existing Detached Accessory Building or Structure Conversion.a.Conforming Detached Accessory Building or Structure.i.An existing Detached Accessory Building or Structure that complies with the setback requirements in Section 11-30-17 (Detached Accessory Buildings or Structures) but does not comply with the setback requirements in Subsection (D)(1) above may be converted to an ADU without requ...
Looking for Maricopa County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Mesa city rules.
Accessory Structures in Maricopa County →