Professional ADU Services

In most of the cities we serve, yes. Arizona House Bill 2720 was signed in May 2024 and took effect on 1 January 2025. It requires municipalities with 75,000 or more residents to allow at least one attached and one detached accessory dwelling unit on single-family residential lots. Phoenix, Mesa, Chandler, Glendale, Scottsdale, Gilbert, Tempe, Peoria, Surprise, Avondale, Goodyear, Buckeye, Queen Creek, Maricopa and San Tan Valley all clear that threshold. Smaller towns are not covered by the mandate and set their own rules, so we check the local ordinance before designing anything.

In Arizona the words are used loosely and often interchangeably. The practical distinction is that an ADU is a complete independent dwelling with its own kitchen, bathroom and entrance, and can normally be rented. A casita is often a guest suite without a full kitchen, which usually places it in a different permitting category. Which one you are actually building changes the permit, the utility connections and what you may legally do with it, so it is worth settling at the first conversation rather than at inspection.

Under HB 2720 a city cannot impose development standards on an ADU that are more restrictive than those already applying to single-family homes in that zone, and height limits must match those for the main structure. Design and material matching requirements vary by jurisdiction, and an HOA can still enforce its own architectural review separately from the city. We submit both together rather than in sequence.

It depends on the design and the jurisdiction. Some ADUs run off the existing house services, others need their own meter, and on a property using septic rather than sewer the added bedrooms can push the system beyond its designed capacity. That last one is the constraint people find latest and dislike most, so we establish the septic and service position before drawings are worth paying for.

The build itself is the predictable part; the review is not. Plan review timelines differ substantially between a large city department and a small town or county office, and an HOA committee adds its own cycle on top. We give you a programme with the review window built into it rather than a construction duration that assumes paperwork takes no time.