ADU Construction in Flagstaff

Almost certainly, yes. Flagstaff allows up to two ADUs on a lot with a single-family home — one detached plus one attached or interior unit. No extra on-site parking is required. The main exceptions are HOA restrictions, which can be stricter than city zoning, and tight lots where setbacks or utilities get complicated. We confirm all of this in a free site walk before you commit to anything.

Detached ADUs in Flagstaff typically run $286–$428 per square foot all-in, so a 600 sqft casita generally lands in the $170K–$260K range and an 800 sqft unit roughly $230K–$340K. Garage conversions and attached units usually cost less because the foundation and shell already exist. We'll give you a line-item budget after the site walk — no surprises mid-build.

Plan on 4–8 weeks for design and permitting (less if we use a pre-approved city model plan) and 4–6 months of construction for a detached unit. Winter weather can affect foundation and framing schedules, which is why we plan the build calendar around it from day one.

Yes — long-term rentals (90-day leases or month-to-month) are allowed outright. If you want to use it as a short-term vacation rental, city rules require you to live on the property yourself. One thing you can't do: sell the ADU separately from your main house.

The city maintains a library of pre-approved ADU designs that can speed up permitting and cut design costs. They're a great fit if one matches your lot and needs. If not, we design custom — and because we know what the city looks for, our custom plans move through review cleanly too.

Detached ADUs can have separate connections. Attached and interior ADUs are required to share utility connections with the main house (internet, TV, and phone excepted). We handle utility planning during design so there are no change orders later.

Your assessed value will increase because you've added livable square footage, but in most cases the rental income or added resale value far outweighs the tax bump. Your county assessor can give you an estimate; we're happy to walk through the numbers with you.

Yes — all of them. Building permit, plan review responses, and inspections are part of every ADU contract. You sign; we handle the rest.