Glendale, AZ Accessory Structures: ADU Rules (2026)

Section 35.3.204(A) of the Glendale Code of Ordinances defines an accessory dwelling unit as a secondary living unit with its own kitchenette, bathroom and sleeping area, independently accessed and located on the same lot as a single-family detached home, either attached or in a separate building; an ADU never counts toward maximum density. It goes through zoning clearance under Section 35.6.210 rather than a full rezoning, is permitted by right anywhere a single-family dwelling is allowed, and cannot be built before the primary house exists. A lot may hold one attached and one detached ADU; a single-family lot of one acre or more can add a second detached ADU if at least one of the units is recorded as restricted-affordable housing. An ADU can never sit on the same lot as a duplex or other multifamily development, and a mobile home, RV or other movable habitable space cannot serve as one.

Setbacks track the underlying zoning district except the code sets its own floors: a minimum 5-foot rear setback, a minimum 5-foot side setback, and a front setback no closer than the district's standard front yard. An ADU must also stay within the district's allowable building frontage, maximum lot coverage and maximum height, and its gross floor area can equal the primary house's footprint but never exceeds 1,000 square feet. No extra parking space or in-lieu parking fee applies, but the unit cannot have its own separate driveway from the primary dwelling. ADUs cannot be sold or conveyed separately from the primary home on the same lot, and any unit built off-site must be placed on an approved permanent foundation system.