Last updated: November 5, 2026
Short answer: To know if a casita or patio cover is permitted in Avondale, AZ, ask the seller for the permits and final inspections, then check the city's permit records. It matters because Avondale says the current owner is responsible for unpermitted work, even work a previous owner did. A casita people live in also needs a Certificate of Occupancy.
Key takeaways
- Avondale says you need plans and a building permit to build, change or use a structure on a single-family lot, including a casita.
- A casita (accessory dwelling unit) needs a Certificate of Occupancy before it can legally be lived in.
- If work was done without a permit, the current owner is responsible for fixing it, even if a previous owner built it.
- Ask for permits early, during your inspection period, and check the city's online records.
Want to talk it through? Book a time to chat with me (30 minutes, 9 AM–7 PM Arizona time).
¡Qué tal! I'm Rosie Armenta. A casita out back or a big covered patio can be exactly what makes a home feel right, especially if you're moving here and picturing guests visiting or a home office. Before you count on it, find out if it was built with permits. Here's how to check, and why it matters to you as the next owner.
Why does it matter if a casita or patio cover has permits?
The City of Avondale's guide to permitting an accessory dwelling unit (ADU) says that if unpermitted work was done to create one, the current property owner is responsible. That includes correcting the work, paying any fees or fines, and bringing the structure up to the city's current building and zoning codes, even if a previous owner built it. If the city finds unpermitted work, its Code Compliance Division can issue a Notice of Violation.
So the question isn't only "Is this nice?" It's also "Would I be inheriting a project?"
What needs a permit in Avondale?
Avondale's ADU guide says you need to submit building plans for review, leading to a building permit, if you plan to build, change or use any space or structure on a single-family property. It lists:
- Building a casita or other accessory dwelling unit.
- Remodeling the home.
- Converting any part of the property into living space, such as a garage.
- Work on electrical, gas, mechanical or plumbing systems.
That "any structure" language is why patio covers belong on your list, too. What a specific patio cover, wall or shed needs can depend on the project, so call before you assume. Avondale Development Services is at (623) 333-4000.
What's the difference between a permitted and an unpermitted casita?
| Permitted casita | Unpermitted casita | |
|---|---|---|
| Building permit and inspections | Issued and passed | Missing or never finished |
| Certificate of Occupancy | Issued, so it can be lived in | Not issued, so it can't legally be lived in |
| Who handles fixing problems | Already handled by a past owner | The current owner (after closing, that's you) |
| What to ask for | Permit numbers and final inspection | Whether the seller will permit it, fix it or adjust the price |
Avondale's guide says you may occupy a new ADU only after all required city inspections are approved and the city issues a Certificate of Occupancy.
How do I check permits for a home in Avondale?
- Ask the seller. The Arizona Department of Real Estate's Buyer Advisory tells buyers to request copies of permits, invoices or other documents for work the seller did, such as an added room.
- Search the city's records. Avondale uses an online permit portal, Accela Citizen Access, with a building permit search. You can also call Development Services or make a public records request.
- Ask your home inspector to look at the casita, patio cover and any additions. My post on what happens at an Arizona home inspection explains what an inspector looks at.
- Compare square footage. The Buyer Advisory says square footage in county records is often only an estimate, so ask how the space was counted.
What the seller must tell you is covered in my post on what sellers have to disclose in Avondale.
What does Arizona law say about casitas?
Arizona's accessory dwelling unit law (A.R.S. 9-461.18) applies to cities with more than 75,000 people. It says those cities must allow at least one attached and one detached ADU on a lot where a single-family home is allowed. An ADU can be up to 75% of the main home's floor area or 1,000 square feet, whichever is less. The law also says:
- The city can't require extra parking for an ADU.
- The city can't set rear or side setbacks of more than five feet for an ADU.
- Building and fire codes still apply.
- Private restrictions, such as HOA rules, aren't prohibited by this law.
- Some lots near military or certain other airports are excluded.
So even where the city allows a casita, your HOA's rules may not. Read the CC&Rs before you plan on adding one.
What if the casita or patio cover wasn't permitted?
You have choices, and they depend on your contract and the seller. Here's a made-up example.
Example only: made-up round numbers, not real Avondale prices.
| Example only | Option A | Option B | Option C |
|---|---|---|---|
| Made-up estimate to permit and fix the patio cover | $8,000 | $8,000 | $8,000 |
| What happens | Seller permits and fixes it before closing | Price drops by $8,000 | You cancel within your inspection period |
| What to ask for | Final inspection from the city | New price in writing | Cancellation notice on time |
A contractor's estimate and a call to the city help you know the real cost. The Buyer Advisory notes that a contractor's license is generally required unless the job is under $1,000, minor and needs no permit, so check the license of anyone who did or will do the work.
How do I check a casita or patio cover before I buy, step by step?
- Ask the seller for permits. Permit numbers, plans and final inspection records for the casita, patio cover and any additions.
- Search the city's permit records. Use Avondale's online portal or call Development Services at (623) 333-4000.
- Have it inspected. Ask your home inspector to look closely at the structure, wiring and plumbing.
- Check the HOA rules. Read the CC&Rs for limits on casitas, patio covers and rentals.
- Get estimates if something's missing. Talk with a licensed contractor and the city about what it would take.
- Negotiate in writing. Put any repair, price change or credit in the contract, before your inspection period ends.
Moving from out of state? I do live video tours, so you can see the casita and the patio up close in real time.
Save this before you fall for a backyard casita.
Related questions I get a lot: new build or resale homes in Avondale and buying a home in Avondale from out of state.
Found a home with a casita or patio cover you love? Book a time to chat with me (30 minutes, 9 AM–7 PM Arizona time), or call or text me at 623-295-5770.
Frequently Asked Questions
Do I need a permit for a casita in Avondale, AZ?
Yes. Avondale's ADU guide says you need building plans, zoning review and a building permit before you build one, and a Certificate of Occupancy before anyone lives in it.
Who is responsible for an unpermitted casita after I buy?
The City of Avondale says the current owner is responsible for correcting unpermitted ADU work, including fees or fines, even if a previous owner built it.
How can I look up permits for a house in Avondale?
Ask the seller for copies, search the city's online permit portal (Accela Citizen Access), or call Avondale Development Services at (623) 333-4000.
Does a patio cover need a permit in Avondale?
Often, yes. Avondale's guide says building, changing or using any structure on a single-family property goes through plan review and a building permit. Call Development Services to confirm.
Can I rent out a casita in Arizona?
State law says cities over 75,000 people can't prohibit long-term rental of an ADU, but HOA rules and city requirements still apply. Check both first.
How big can a casita be in Arizona?
Under A.R.S. 9-461.18, cities covered by the law must allow an ADU up to 75% of the main home's floor area or 1,000 square feet, whichever is less.
Can my HOA stop me from building a casita?
The state ADU law doesn't prohibit private restrictions between private parties, so your HOA's CC&Rs may limit casitas. Read them before you plan one.
Should I buy a home with an unpermitted patio cover?
It depends on the cost to fix it and what the seller agrees to. Get an estimate, ask the city and negotiate during your inspection period.
I'm a real estate agent, not a building official, a contractor or an attorney. I can't tell you whether a specific structure meets code or what the city will require. Please confirm with Avondale Development Services and a licensed contractor.
This article is general information, not legal, tax, or financial advice. Please talk with a licensed attorney, CPA, or lender about your situation.
About the author
Rosie Armenta | West USA Realty. Avondale (85392) is her home base, and she helps buyers and sellers across the West Valley in English and Spanish. Book a time to chat with me (30 minutes), or call or text 623-295-5770. Selling? Get a home value report.
Rosie Armenta | West USA Realty | Equal Housing Opportunity
Information was checked on November 5, 2026, from the City of Avondale guide "Permitting an Accessory Dwelling Unit in Avondale" (May 2026), the City of Avondale Accela Citizen Access portal, Arizona law A.R.S. 9-461.18 and 32-1121, and the Arizona Department of Real Estate Buyer Advisory (January 2025). City rules can change, so please confirm your project with Avondale Development Services.