Flagstaff, AZ Accessory Structures: ADU Owner Occupancy (2026)

Zoning Code Section 10-40.60.030's Required Occupancy standard, part of Table 10-40.60.030.A that governs ADUs citywide, ties short-term rental of an ADU directly to owner presence on site. The immediately preceding provision allows the primary Single-Family Dwelling and any ADU on the same lot to be leased separately from each other as long-term rental housing, defined as a lease of 90 days or longer or a month-to-month tenancy. The owner-occupancy clause is the trade-off for going shorter than that: when a property contains an ADU and that ADU is used as either a vacation or short-term rental, the property owner must reside on the property.

That sits within a broader set of ADU controls in the same section, including a two-person occupancy cap per ADU, a ban on selling an ADU separately from the primary structure, a prohibition on using a mobile home, recreational vehicle, or other movable habitable space as an ADU, and a size cap of the lesser of 75 percent of the primary dwelling's gross floor area or 1,000 square feet (with an 800-square-foot floor regardless of house size). The owner-occupancy requirement gives Community Development a bright-line test for short-term rental complaints tied to ADUs: either the owner lives there, or the ADU has to be rented long-term instead.