It has Become Easier to have Another Dwelling on Your Property | Arizona’s HB 2928

Natalie Fricke
Sep 18
2 min read

Arizona just passed HB 2928, a law that could change how housing looks in many communities. It’s a long, technical bill—but at its core, it’s about making it easier to add Accessory Dwelling Units (ADUs) and giving cities less power to block them.

First, What’s an ADU?

Think of an Accessory Dwelling Unit as a small, independent home on the same lot as a single-family house.

A casita or guest house
A basement apartment
A garage converted into a studio

They usually have their own kitchen, bathroom, and entrance, and can be rented out or used for family.

Key Takeaways from HB 2928

Every qualifying city must allow ADUs.If a town has more than 75,000 people, it has to make space in its zoning for at least one attached and one detached ADU on any lot zoned for single-family homes.
Extra allowance on larger lots.If you’ve got at least an acre, you may be able to build a second detached ADU—as long as one of them is affordable housing.
Size rules.An ADU can be up to 75% the size of your main house, capped at 1,000 sq. ft.
No extra parking hoops.Cities can’t force you to add more parking spots (or pay fees) just because you’re adding an ADU.
Design freedom.You don’t have to match roof pitch, paint color, or siding with your main house.
Fair zoning.Setbacks, height limits, and lot coverage rules for ADUs can’t be stricter than what’s already applied to single-family homes.
No “family only” rule.You don’t need to be related to someone to rent or live in an ADU on your property.
Rental flexibility.You can lease your main home and ADU separately for long-term rentals (90+ days).
Short-term rentals also covered.HB 2928 tweaks the rules around Airbnbs/VRBOs, letting cities regulate health and safety but not ban them outright.

Why This Matters

Arizona has a housing shortage. Prices and rents have soared, especially in the Phoenix metro. HB 2928 tries to tackle that by:

Adding supply: More ADUs mean more places for people to live.
Encouraging affordability: Some ADUs must be rented below market rate.
Helping families: Think multigenerational living—grandparents, young adults, or caregivers right on the property.
Creating income streams: Homeowners can rent an ADU for extra income.

Real-Life Example

Imagine a Gilbert family with aging parents. Instead of moving mom and dad to an assisted living facility, they could build a 600 sq. ft. casita out back—close enough for support, but private enough for independence.

Or picture a young couple saving for their first home. Renting a backyard ADU might offer affordable housing in a neighborhood they love.

What’s Next

Cities over 75,000 people must update zoning by January 1, 2025.
If they don’t, ADUs are automatically allowed—no limits.
Smaller towns aren’t required, but some may choose to follow.

The Big Picture

HB 2928 is Arizona’s way of nudging cities toward more flexible, inclusive housing. It won’t solve everything overnight, but it opens doors—literally—for more options in how we live and use our space.

As this rolls out, the real test will be whether homeowners embrace ADUs, how cities manage the growth, and whether it actually eases the housing crunch.