Accessory Dwelling Units (ADU)

Check your HOA rules about accessory structures.

When a lot has no more than one single-family detached primary dwelling, two ADUs are permitted in addition to the primary dwelling unit. A third ADU may be pemittd under certain circumstances. Typical single-family zones are: R1-6, R-1-10...etc.

Use My Community Map​ to find out the zoning district for your home. 

​Each zoning district has “lot coverage" guidelines that define how much of your property can be covered by buildings or structures. The new guest house rules allow two ADUs per lot (and even three on certain lots), and each ADU may be up to 75% of the gross floor area of the main house (not to exceed 1,000 sf for lot up to 10,000 sf or 3,000 sf for lots over 10,000 sf).

In My Community Map​, link to the Phoenix Zoning Ordinance to determine the lot coverage allowance for your home. 

​​Find your property on the Maricopa County Assessor's Office website. It will list your official lot size as well as the dimensions of the structures on your property. You can use these two figures to make a rough calculation of your current lot coverage.