AGrannio

Can You Build an ADU in Tempe?

Yes — Tempe is governed by Arizona's statewide ADU law, which limits what the city can restrict. A 700 sq ft detached ADU here runs about $151,000–$247,000.

Construction costs in Tempe track close to the Arizona state average.

Detached ADU (700 sq ft)

$151,000–$247,000

Garage conversion (400 sq ft)

$47,000–$86,000

Statewide protection

Yes

What applies in Tempe

Arizona's statewide standard (Arizona HB 2720 (2024)) is the starting point, but parcel-level rules, fees and design review are set locally. Confirm those details with Tempe before design.

Estimate your Tempe ADU cost

Your property

ADU type

Estimated cost in Arizona

$151,000 – $247,000

≈ $216–$353/sq ft turnkey · midpoint $199,000

$135,300
Construction
$35,800
Design & permits
$27,900
Site work
Good news — building an ADU in Arizona is very likely allowed.
  • iSize set locally. This state leaves ADU size limits to your city — typical caps run 600–1,200 sq ft. Check your local code.
  • ✓No extra parking likely required. Set by local ordinance — commonly 1 space per ADU unless near transit.
  • iOwner-occupancy varies. Owner-occupancy rules are set locally in this state.
  • ✓Lot has room. A 700 sq ft ADU uses about 12% of your 6,000 sq ft lot — comfortably within typical coverage limits.

Rule basis: Arizona HB 2720 (2024)

If you rent it out

$1,050–$1,700

est. rent/mo

8.3%

gross yield

13 yrs

payback

~$15,345/yr after a 7% vacancy allowance, before financing & maintenance.

Financed over 20 yrs at 7.5%, the build is about $1,603/mo — vs ~$1,375/mo in estimated rent.

Get your detailed feasibility report →

Estimates are for planning only and are based on regional construction-cost indices and published statewide ADU statutes. Local ordinances, lot conditions and contractor pricing vary — always confirm with your city planning department and a licensed contractor.

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Other Arizona cities

PhoenixTucsonMesaChandlerScottsdaleGilbert

Estimates are for planning only and are based on regional construction-cost indices and published statewide ADU statutes. Local ordinances, lot conditions and contractor pricing vary — always confirm with your city planning department and a licensed contractor.