Scottsdale’s ADU rules at a glance
| Scottsdale ADU rule | What the city says |
|---|---|
| How many | One attached and one detached ADU per single-family lot. A third detached ADU is allowed on lots of one acre or more if one unit is restricted-affordable. |
| Size | First ADU: 1,000 sq ft or 75% of the main home, whichever is less. Second and third: 500 sq ft. |
| Placement | Detached ADUs may not sit in a required front or side yard. In the rear yard they can be as close as 5 ft to a side or rear lot line, and must be at least 10 ft from the main home and other ADUs. |
| Height | Limited to the maximum for the property’s zoning district. |
| Utilities | Separately metered electric and gas service for each ADU. |
| Access | Its own exterior entrance, a path to the street, and its own visible address. |
| Outdoor space | At least 50 sq ft of private outdoor space, 5 ft deep. |
| Renting | The owner must live on the property if any ADU is rented or used as a short-term rental. |
| Other | No more than six adults across the main home and all ADUs. ADUs cannot be sold separately. Parking for the main home must be kept. |
Source: City of Scottsdale ADU page (Ordinance 4687, adopted September 30, 2025). HOA rules can add requirements on top.
Planning a detached ADU on your lot
Placement
Rear-yard placement usually gives the most flexibility. Check easements, washes, existing trees, the pool and sightlines to neighbors before settling on a spot.
Utilities
Separate electric and gas meters are required, so plan service routes early. Sewer connections, or septic capacity in areas without sewer, often decide where the unit can go.
Size and layout
With a cap of 1,000 sq ft (or 75% of the main home), most detached ADUs are studios, one-bedrooms or compact two-bedrooms. Good storage, a full kitchen and a laundry spot make a small unit livable.
Access
The city requires a path from the ADU to the street and a unique, visible address. Plan lighting and a gate so tenants or family can come and go easily.
Building for the desert
- Orient windows to limit west sun and add shade on the patio.
- Insulate the roof well. It is the biggest source of summer heat.
- Size cooling for the unit, often a ductless mini-split.
- Use durable, easy-clean finishes if the unit will be rented.
Renting your ADU
Scottsdale requires the owner to live on the property for any ADU that is rented or used as a short-term rental. Short-term rentals also follow Zoning Ordinance Sec. 7.203.
Prefer a unit joined to the house? See attached ADU construction. Building for family? See in-law suites.
