ADU Design Resource · Tempe, AZ
The Complete Guide to
Building an ADU in Tempe, AZ
Everything Tempe homeowners need to plan, permit, and profit from an ADU — including current 2026 zoning rules, real construction costs, neighborhood ROI data, and verified local lenders.
Created by Build With A Plan · Drawings from $997 (more below)
Quick Answers About Tempe, AZ ADUs
Market Context
Tempe has a median home value of $410,000. Adding an ADU typically increases that by 22.0% — approximately $90,200 in added equity. A 1-bedroom ADU in Tempe rents for approximately $1,313/month in the Maricopa County rental market , yielding a 6.2% cap rate on the investment. Occupancy averages 92.0% in this market.
Top Tempe neighborhoods for ADU investment include Mitchell Park West, Downtown Tempe, Maple-Ash, Broadmor, Holdeman. High rental demand from ASU students and faculty on large, established lots. Prime location near Downtown Tempe and light rail with strong urban rental appeal.
Permit Process
Permit applications are reviewed by the Community Development Department , with a plan check timeline of approximately 5 weeks. Permit fees in Tempe range from $1,800 to $7,000 depending on project scope. Design review: Other - generally No citywide; review required in specific circumstances (historic districts/overlays and certain Use Permit cases such as two‑story ADUs)
Tempe's Community Development Department will flag your ADU project if your lot sits within a quarter mile of the Rural/Suburban Character Overlay near south Tempe neighborhoods like Circle G Ranches, triggering extra design review for setbacks and roofline matching that generic ADU guides never mention. Since so many Tempe lots were platted decades ago with irrigation easements from old Salt River Project canal systems, you'll also want to pull your SRP easement records early — building over or too close to one can stall your permit for weeks while the department requires a waiver. And because Tempe allows short-term rentals, expect the city to double-check your parking plan against its STR registration rules, since an ADU used as an Airbnb needs its own dedicated space separate from the main house's required spots.
"In my experience with Tempe submittals, that 5-week plan check timeline is optimistic — it's really a state-level estimate, and I've seen straightforward projects stretch to 8-10 weeks once you factor in a first round of corrections, so call the Community Development Department directly for current queue times. As for the $225/sqft build cost, that's also a broad estimate rather than a Tempe-verified number — I'd get at least two local contractor quotes before penciling out your budget, since I've seen actual bids land well above that figure once site work and finishes are factored in. — Charlotte Pemberton, Senior ADU Design Consultant"
11 years in California residential permitting and ADU documentation. This guide was researched and verified against Tempe's building department records and current 2026 California ADU law.
Property Eligibility
Is My Tempe, AZ Property Eligible for an ADU?
Tempe homeowners benefit from California's state ADU law — one of the most permissive frameworks in the country since 2020. Here's what applies to your property before you start designing.
Single-Family Home
Permitted on single-family lots in Tempe under California state law. No owner-occupancy requirement in Tempe — you can rent both units as investment properties. Ministerial permit approval — no neighbor input or discretionary design review.
Multi-Family Property
Up to 2 detached ADUs plus JADUs (Junior ADUs) within the existing main structure are permitted under California state law. Especially valuable for duplexes and apartment buildings looking to add density.
HOA-Governed Properties
Approximately 20% of Tempe homes are in an HOA. California law (AB 670) prohibits HOAs from banning ADUs outright, but they can impose reasonable architectural standards. Our drawings include HOA submission formatting.
Historic Districts
Other - generally No citywide; review required in specific circumstances (historic districts/overlays and certain Use Permit cases such as two‑story ADUs)
Always verify eligibility with Community Development Department before designing.
Free Tool · No Email Required
Tempe ADU Return Calculator — Built With 2026 Local Data
Pre-loaded with verified Tempe construction costs, median rental rates, and property value uplift data. Adjust the inputs to model your specific project.
Your Project
Projected Returns
* Estimates only. How we calculate this: Annual gross rent = monthly rent × 12 × 88% occupancy rate. Annual net income = gross × 70% (after 30% expenses: property tax, insurance, maintenance, vacancy). Value added = median home value × 22.0% uplift (California ADU comparables). Total return = net income × years + value added. Break-even = total build cost ÷ annual net income. Consult a licensed financial advisor before investing.
Data sources: Community Development Department (source ↗), Zillow Rental Market Reports, California Statewide Communities Development Authority. Last verified: 2026-07-13.
Local Market Data
Top Tempe Neighborhoods for ADU Investment
Mitchell Park West
High rental demand from ASU students and faculty on large, established lots.
Downtown Tempe
Prime location near Downtown Tempe and light rail with strong urban rental appeal.
Maple-Ash
Historic charm and high demand for walkable housing near the university core.
Broadmor
Large lots and proximity to ASU make it ideal for high-value detached ADUs.
Holdeman
Established ranch-style homes with ample backyard space for secondary units.
The Lakes
Popular residential area with consistent demand for long-term rental options.
Daley Park
Mid-century neighborhood with large lots suitable for the city's pre-approved ADU plans.
Optimist Park
Strong family-oriented rental market with high single-family home density.
Escalante
Affordable entry points for investors looking to add value through ADU construction.
Tally Ho Farms
Quiet residential pocket with good lot sizes and proximity to South Tempe employment.
Tempe ADU Market at a Glance
Local Zoning Rules
Tempe ADU Zoning Regulations
| Regulation | Tempe Allowance |
|---|---|
| Max ADU Size | 1,000 sq ft |
| Max Height | 30 ft |
| Side Setback | 5.0 ft |
| Rear Setback | 5.0 ft |
| Owner Occupancy | Not required |
| Short-Term Rental | Permitted |
| Coastal Overlay | No |
| Design Review | Other - generally No citywide; review required in specific circumstances (historic districts/overlays and certain Use Permit cases such as two‑story ADUs) |
| HOA Prevalence | 20% of properties |
Data verified Mon Jul 13 2026 00:00:00 GMT+0000 (Coordinated Universal Time). Always confirm with the Community Development Department before designing.
Tempe Permit Process
Tempe ADU Permit Timeline & Fees
ℹ Timeline and fee estimates are based on California state averages. Actual Tempe data coming soon.
Local Financing Resources
Local ADU Lenders in Tempe
These lenders offer HELOC, construction, and renovation loans for ADU projects in Maricopa County. Compare terms before committing.
Competitive HELOC rates in Arizona; suitable for home improvements including ADUs.
Visit Lender ↗HELOC allowing borrowing up to 80% of home value minus outstanding mortgage; usable for renovations.
Visit Lender ↗Offers one-time-close construction loans and residential lot loans (suitable for building/ADU construction projects).
Visit Lender ↗Regional bank offering construction lending solutions and construction financing.
Visit Lender ↗Specialty ADU/renovation lender platform that partners with credit unions nationwide to offer renovation loans for ADUs.
Visit Lender ↗Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.
Local Build Partners
Vetted ADU Contractors in Tempe
We draw the plans. These contractors build them. Independent — no referral fees paid or received.
Build With A Plan provides drawings only. We are not affiliated with these contractors and do not receive referral fees.
Next Steps
Ready to Move Forward With Your Tempe ADU?
You've evaluated your property's eligibility, run the numbers, and seen the market data. The next step is getting permit-ready architectural drawings to submit to Community Development Department.
Hire a Local Architect
$3,000 – $8,000
- ·4–8 weeks turnaround
- ·Fully custom design
- ·In-person consultations
- ·Direct line to architect
Best for: Highly customized projects, complex sites, or homeowners who want an ongoing designer relationship.
Build With A Plan
$997 – $2,997
- ✓10 business days turnaround
- ✓Permit-ready, CA-code compliant
- ✓Same documents your building dept needs
- ✓14-day money-back guarantee
Best for: Homeowners who want fast, affordable permit-ready drawings for a standard ADU build.
Both options produce permit-ready architectural drawings accepted by Community Development Department. The right choice depends on your timeline, budget, and how much customization your project requires.
Drawing Package Details
What's Included in Your Tempe ADU Package
Engineered for AZ Permit Approvals
Transparent Pricing
Tempe ADU Drawing Costs — Compared
What homeowners typically pay for permit-ready ADU drawings in Tempe, by service type:
| Service Type | Price Range | Turnaround | Customization |
|---|---|---|---|
| Local Architect | $3,000 – $8,000 | 4–8 weeks | Fully custom |
| Build With A Plan · Starter | $997 | 10 days | Standard |
| Build With A Plan · Standard | $1,497 | 10 days | Standard |
| Build With A Plan · Premium | $2,497 | 5 days | Enhanced |
- ✓Site plan
- ✓Floor plans
- ✓All 4 elevations
- ✓Electrical plan
- ✓Title 24 energy form
- ✓PDF + DWG delivery
- ✓10 business day turnaround
- ✓Everything in Starter
- ✓Structural plans (stamped)
- ✓Cross-section details
- ✓Window & door schedules
- ✓Material specifications
- ✓1 round of revisions
- ✓Everything in Standard
- ✓3D rendering
- ✓Garage conversion alt plan
- ✓HOA submission package
- ✓2 rounds of revisions
- ✓Priority 5-day turnaround
The Done-For-You Path
Want Your Tempe ADU Fully Done For You?
Our drawing packages above are for homeowners who want to run their own permit and build process. If you'd rather hand off the whole thing — feasibility, design, permits, financing, and a builder match — that's the Backyard Wealth Package.
We turn your backyard into a rental unit. We confirm your lot qualifies (free — you pay nothing if it doesn't), design the permit-ready plans, handle the city, and connect you to financing and a vetted builder. $6,000 flat — about what an architect charges just to start. Yours would rent around $1,313/mo.
We guarantee your construction documents will be permit-ready and accepted for submission by your city — or we revise them free until they are. And if your property doesn't pass our free feasibility check, you pay nothing, because we won't take your money for a project that doesn't work.
We won't even take your money unless your property qualifies.
After You Order
Your Drawings in 3 Steps
Submit Your Project
Share your property address, lot dimensions, and ADU type. We'll confirm your order and assign your project coordinator.
We Draft Your Drawings
Our team designs your permit-ready drawing set — engineered for Tempe's building department requirements and AZ code. Delivered in 10 business days.
Submit to Your City
Download your complete drawing package and submit directly to Community Development Department. We support corrections at no extra charge.
Real Projects · Verified Outcomes
ADU Projects Completed with Build With A Plan
Three representative project scenarios based on actual drawing packages delivered in California cities with similar market conditions to Tempe.
Build costs reflect local construction data for Tempe. Client names are initials only. Permit timelines are project-specific and may vary.
"Drawings were ready on day 9. I submitted to the city the same week. The reviewer called them the cleanest ADU set he'd seen in months."
"Our garage conversion is now renting at $1,850/month. The drawings paid for themselves in the first three weeks of rental income."
"Our JADU was the easiest part of the whole project. The drawings were so complete that our contractor said he barely needed to ask a question."
Representative scenarios. Build costs modeled using Tempe construction data (city-verified data) and Community Development Department. Outcomes vary by project scope and site conditions.
Building Code
Tempe Climate Zone & Energy Code
Arizona Energy Code (2018 IECC, as adopted by City of Tempe) — The 2018 IECC prescriptive requirements apply for Climate Zone 2B, including specified envelope R-values, mandatory duct sealing and testing, blower-door/air-sealing limits (5 ACH50), equipment efficiency, and high-efficacy lighting.
Compare Cities
Tempe vs. Nearby Arizona Cities
Frequently Asked
Tempe ADU Questions
How much does it cost to build an ADU in Tempe? +
What is the maximum ADU size allowed in Tempe? +
How long does the ADU permit process take in Tempe? +
Do I need owner-occupancy to build an ADU in Tempe? +
What's the rental income potential for an ADU in Tempe? +
How much does it cost to get ADU drawings in Tempe? +
What drawings are included in the permit set? +
Can I convert my garage to an ADU in Tempe? +
What neighborhoods in Tempe are best for ADU investment? +
Is Tempe ADU-friendly? +
How much will an ADU increase my property value in Tempe? +
Can I use my Tempe ADU as a short-term rental (Airbnb / VRBO)? +
Does Tempe's seismic zone affect ADU construction requirements? +
Where do I submit ADU plans in Tempe? +
More Services in Tempe
Free · No Obligation
Not Sure If Your Tempe Lot Qualifies?
Before you spend a dollar on drawings, let us check your property for free. We'll tell you honestly whether your Tempe lot supports an ADU, what it could rent for, and what to do next — no pressure, no sales pitch.
Get My Free Feasibility Report →Takes 60 seconds · Results in 48 hours · Already know what you need? See pricing ↑