Looking for accessory dwelling unit new hampshire 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.

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Frequently asked in Phoenix

What are the disadvantages of ADUs in Phoenix?

Some potential disadvantages of ADUs in Phoenix might include the initial investment in construction and ensuring compliance with local zoning and building codes. Homeowners may also consider the impact on property drainage and landscaping in our arid climate. However, these can be effectively managed with expert planning. We can help you explore options.

How much does an ADU cost in Phoenix?

The cost of an ADU in Phoenix depends on factors like its size, the chosen materials, and site preparation needed. Your specific location within the Phoenix area and any required utility upgrades will also affect the price. For an accurate estimate tailored to your project, a personalized quote from a professional is the best approach. We can help you get one.

What are the rules for ADUs in Phoenix?

Is an ADU allowed in my Phoenix neighborhood?

ADUs are generally permitted in many residential zones throughout Phoenix, but specific requirements must be met based on zoning and property characteristics. It's essential to confirm eligibility with someone familiar with local codes. The pros can quickly assess your property's suitability and advise on what's possible. Let's confirm for your specific address.

What is the process for building an ADU in Phoenix?

Can I add an ADU to my existing Phoenix home?

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

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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, Biltmore, Ahwatukee, Paradise Valley, Scottsdale, Tempe — and every surrounding area.