RVs and Manufactured Homes Could Become Backyard Casitas in Mesa

Mesa is considering a new way to expand affordable housing options: allowing homeowners to place manufactured homes and possibly recreational vehicles in their backyards as accessory dwelling units (ADUs), often called casitas.

Supporters say it could be a faster, simpler, and sometimes cheaper path to adding housing. Opponents argue it could create serious fire-safety challenges and change how neighborhoods feel and function.

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Why Mesa Is Talking About This Now

A new Arizona state law took effect in January. It requires cities with more than 75,000 residents to allow at least one attached and one detached ADU on single-family lots. Mesa has permitted ADUs for decades and updated its ordinance last fall to better align with the new requirements.

Mesa’s current ADU rules allow conventional stick-built units. They also allow certain factory-built tiny homes if they sit on a permanent foundation. The ordinance does not override HOA rules that prohibit or restrict ADUs.

What’s Being Considered: Expanding the Types of ADUs

Mesa currently allows manufactured homes and recreational vehicles (including tiny homes on wheels) as dwelling units only in mobile home or RV parks and certain subdivisions. City leaders are now exploring whether those housing types could be allowed as backyard casitas on single-family residential lots.

The city’s Community and Cultural Development Committee voted 2–1 to move the idea forward for full council discussion. The council is expected to hear the issue in May.

Councilwoman Julie Spilsbury, who chairs the committee, said she supports giving homeowners more options:

“I like the opportunity for more options for homeowners. I think this is a quicker, easier way and in some cases cheaper way to make that happen. It’s a great option, actually, for our housing crisis that we’re in.”

The Case For It: Speed, Flexibility, and Potential Affordability

City staff said adding manufactured homes, park models, or other movable units to the menu of ADU options could increase housing diversity and reduce costs for some homeowners and renters.

Principal planner Cassidy Welch told the committee that these units can be obtained more quickly than a traditional backyard build and that newer models can be energy efficient. She also said expanding options could increase affordability for the ADUs themselves and potentially reduce rent pressure overall.

Supporters see a practical upside: if a homeowner can place a ready-made unit on their lot instead of managing a full construction project, more housing could come online faster.

The Drawbacks: Insurance, Financing, Installation, and the “You’re Not Using the Whole Allowance” Problem

Welch also outlined several concerns. Insurance and financing can be more complicated for some units, and there are practical installation hurdles. Getting a manufactured home into the rear of a property can be difficult, especially without alley access. In some cases, the unit may need to be craned into place.

Another trade-off is size. Under Mesa’s ADU ordinance, accessory dwelling units can be up to 75% of the primary residence, or 1,000 square feet. Park models are often closer to 400 square feet. This means homeowners may not be maximizing the square footage they could otherwise build.

How Mesa Compares to Other Valley Cities

Mesa staff said policies vary across the region:

• Phoenix, Tempe, Gilbert, and Chandler allow manufactured homes and park models for ADUs if they have a foundation or are permanently affixed.
• Apache Junction, Queen Creek, and Scottsdale do not allow park models or homes built on wheels (typically 400 square feet and under), RVs, and manufactured homes to be used as ADUs.

City officials noted that none of the surveyed Valley municipalities currently allow RVs as backyard casitas.

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What Happens Next

The Mesa City Council is expected to take up the issue in May. If the city moves forward, homeowners could eventually have a new way to create space for family members, caregivers, or renters, without the cost and timeline of traditional construction.

But the debate highlights the trade-offs Mesa must weigh: faster housing options versus fire access concerns, homeowner flexibility versus neighborhood impacts, and affordability goals versus long-term policy consequences.