What Flagstaff ADU limits and checks matter when evaluating an accessory unit near NAU?

DIRECT ANSWER

Original source observation: October 16, 2026. Primary-source review: October 17, 2026. Confirm current dates, costs, eligibility and availability with the linked publisher. Campus facts and general planning guidance do not determine an individual property's lawful use, employment benefits or mortgage eligibility.

Flagstaff’s ADU Model Plans Library guidance describes ADUs on lots with an existing single-family home, generally up to two units (one detached and one attached or interior). It says ADUs are not allowed on a duplex or multifamily parcel. The guidance limits size to 75% of the main home or 1,000 square feet, whichever is less, with an allowance up to 800 square feet when the other zoning requirements are met; it also states a maximum of two residents per ADU. The City assigns an address during permit review. Ask the City to confirm the actual parcel’s zoning, occupancy, setbacks, utilities and any applicable exceptions, and check HOA restrictions before relying on a model or underwriting rent.