Maricopa County planning staff on Oct. 23 presented an ordinance to implement recent Arizona legislation expanding the allowance for accessory dwelling units (ADUs) and to define short-term rentals; the Planning and Zoning Commission voted 9-0 to recommend approval and forward the ordinance to the Board of Supervisors for the Nov. 19 meeting.

Why it matters: The ordinance would bring county zoning into compliance with state law intended to increase housing availability. It changes how ADUs are regulated, allows certain ADUs as-of-right, sets size and placement limits, and creates new rules for short-term rentals and an affordable-unit requirement for some additional ADUs on large parcels.

Staff summarized the proposal as an emergency ordinance to meet statutory deadlines. Key provisions include: any parcel zoned for a single-family residence and one acre or smaller must allow at least one attached or one detached ADU as a matter of right; ADUs on parcels of one acre or less shall not exceed the size of the primary dwelling, and on such lots the ADU size “shall not exceed 75% or 1,000 square feet, whichever is less.” For parcels of one acre or larger, up to two detached ADUs must be allowed, and the second detached ADU must be restricted to households earning at or below 80% of area median income (AMI).

The ordinance also defines short-term rental as a dwelling or ADU leased for 30 consecutive days or fewer, and adds use restrictions: only one ADU on a parcel may be used as a short-term rental; the owner must reside on the property; rentals may not be used for events, signage, retail food service or commercial enterprises; and rentals may not be leased to registered sex offenders (as stated in the staff presentation).

Commissioners asked several clarifying questions about enforcement and measurement. Commissioner Lindblom asked how the affordability restriction on the second detached ADU for parcels of one acre or more would be enforced; staff said it “will be deed restricted, and it will be on the description of the building permit,” and that the county would require documentation if complaints are filed. On monitoring, a real-estate commenter said there appeared to be no active monitoring; staff replied that enforcement would be complaint-driven and that the deed restriction would be tied to the parcel’s assessor parcel number (APN).

Commissioners also queried parking and driveway access. Staff said the ordinance requires single access to the street (one ingress, one egress) and that state law prohibits requiring additional parking for ADUs beyond existing off-street parking requirements; two off-street spaces are required for the primary residence regardless of ADUs. Staff clarified that the 1,000-square-foot limit refers to the entire space assigned to the ADU and that uncovered patios are not included in that count.

Commissioner Whitney moved to recommend approval; Commissioner Layton seconded. Roll-call votes recorded “yes” from Commissioners Finter, Hernandez, Lawrence, Layton, Chairman Lindblom, Vice Chair Mulhavin, Commissioner Rockwallak, Commissioner Toma and Commissioner Whitney. The motion passed 9-0.

Staff said the ordinance will be considered by the Board of Supervisors on Nov. 19 and that the county is treating the measure on an emergency schedule to meet the state deadline; staff indicated the ordinance would be effective before the end of the year to comply with state law.