Accessory dwelling unit cost — Phoenix, AZ | AccessoryDwellingUnit Services

Looking for accessory dwelling unit cost in Phoenix, AZ? Call AccessoryDwellingUnit Services for a contact a provider — no obligation. Licensed adu builders serve Phoenix and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.

About this service

Total costs for an ADU vary based on the size of the unit, the complexity of the site, and the quality of materials you select for the kitchen and bathroom. Things like trenching for new sewer lines or upgrading your main electrical panel can also impact the bottom line. We provide an exact pricing confirmed free on the call.

Frequently asked in Phoenix

What are the disadvantages of ADUs in Phoenix?

Potential disadvantages can include the initial construction costs and navigating Phoenix's specific building codes and zoning ordinances. Homeowners might also consider the impact on their yard space. It's wise to weigh these factors carefully. We can help you explore your options.

How much does an ADU cost in Phoenix?

What are the rules for ADUs in Phoenix?

Phoenix has specific zoning ordinances and building codes that govern the construction of accessory dwelling units. These regulations address aspects like lot size, setbacks, and the relationship to the primary dwelling. Compliance with these rules is essential. The pros we work with are knowledgeable about these guidelines.

Is an ADU allowed in Phoenix?

Yes, accessory dwelling units are permitted in Phoenix under specific zoning regulations. The city allows for the creation of additional housing units on existing residential properties. It's important to ensure your project meets all the city's requirements and codes.

What are the rules for ADUs in California?

California's ADU laws are designed to encourage their construction, but local cities in California also have their own specific ordinances. These often detail aspects like maximum unit size and parking requirements. Always check with your local planning department. We can help you find relevant information.

California has offered various grant programs aimed at helping homeowners with the financial aspects of building ADUs. These programs typically have specific eligibility requirements and application procedures. It's a good idea to research current state and local funding opportunities.

Also serving nearby: Glendale · Scottsdale · Tempe · Peoria · Surprise

All cities in Arizona →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

1,650,070residents

3,183per sq mile

8ZIP codes served

Serving all of Phoenix — population 1,650,070; about 3,183 residents per square mile across 518.3 sq mi. ZIP codes covered include 85001, 85002, 85003, 85004, 85005, 85006, 85007, 85008.

Neighborhoods served in Phoenix: Arcadia, Scottsdale, Tempe, Glendale, Ahwatukee, Paradise Valley — and every surrounding area.