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Casita design and permits, start to finish

We research the parcel, draw the plans, run the engineering, file with the right office and answer every correction. It is part of every build.

Who reviews my casita?

It depends on the parcel, not the mailing address. A Tucson address can sit in the City of Tucson, in a town, or in unincorporated Pima County:

City of Tucson: Planning and Development Services (PDSD).
Oro Valley, Marana, Sahuarita: each town's own planning and building staff.
Catalina Foothills and other unincorporated areas: Pima County Development Services.

What goes into the plans?

A site plan with every structure, setbacks, easements and lot coverage.
Floor plans and elevations to confirm size against the main home.
Structural design, including footings for caliche where we find it.
Energy and mechanical work to the current code. Tucson's 2024 building code editions took effect January 1, 2026.
Septic sizing where there is no sewer; state law lets counties require an adequately sized system before an ADU is built.

Floor plan and site plan drawings: Person writing on white paper

Do I need a public hearing?

Not inside Tucson, for a qualifying ADU. State law requires cities over 75,000 to allow ADUs as a permitted use, meaning no public hearing, variance or conditional use permit. A staff check that the site plan meets the code can still apply. The same permitted-use approach applies to counties under the 2025 county law.

Are there fees beyond the permit?

Yes, impact fees in many places. In 2023, Tucson PDSD put them at about $2,750 for units of 750 sq ft or less and $4,310 for larger units, as reported by the Arizona Daily Star. Fees are updated over time, so we confirm the current schedule with your quote.

How long does review take?

It depends on the office, the completeness of the submittal and the number of correction rounds. An architect quoted by the Arizona Daily Star in 2023 put the time before construction at about six months, against a goal of one month. Model plans can shorten it. Your written quote includes a schedule.

What can Tucson not demand?

For Tucson, state law rules out added parking, setbacks over 5 feet, design-matching, fire sprinkler mandates and street improvements beyond repairing damage. Building, fire and health codes still apply.

Start with the parcel

Send your address. We find out which office reviews it and what it allows.