ADU vs. Tiny Home: What's the Difference? (2026 Guide)
Quick answer: An ADU is a legal classification — a permitted second dwelling on your lot, usually foundation-set — while a tiny home on wheels is legally an RV in most of Utah. That one difference decides where you can live in it, how you finance it, and whether it adds property value. A Cocoon home starts at $55,000 and can be placed either way.
What legally separates an ADU from a tiny home?
"Tiny home" describes the house itself — a compact dwelling, typically 100–400 square feet. "ADU" (accessory dwelling unit) describes its legal status: a permitted secondary residence on a lot that already has a primary home. A tiny home becomes an ADU when it's permanently placed and permitted as a dwelling. The two labels answer different questions: one is about the building, the other is about the paperwork.
That paperwork matters more in Utah than ever. In 2026 Utah passed SB284, which requires cities with 5,000 or more residents to allow detached ADUs — backyard cottages, standalone guest houses — on lots of 11,000 square feet or larger, with cities required to adopt an ADU policy by October 2026. A permitted ADU is real property: it's inspected, addressed, and part of your home's value.
A tiny home on wheels (THOW) that stays on its trailer is treated differently. Most Utah cities classify a THOW as a recreational vehicle — personal property, like a trailer or motorhome — which means it generally can't be a full-time residence on a standard residential lot.
Which one costs more?
Nationally, professionally built tiny homes on wheels run $70,000–$150,000 according to Clever Tiny Homes' 2026 pricing guide, while foundation-set ADUs commonly land between $80,000 and $200,000+ once site work is included.
Cocoon builds one home that can be either. Our most popular model, the 300 Series — a true one-bed, one-bath at 300 square feet — starts at $78,000. Placed as a towable, that's close to your all-in number. Placed as a permanent ADU, plan on site work (foundation, utility hookups, permits) adding 35–50% on top of the home price — we walk you through every dollar in our Utah ADU cost guide.
Quick comparison: permanent ADU vs. tiny home on wheels
Legal status — Cocoon home as a permanent ADU: permitted dwelling, real property. THOW: RV, personal property.
Where it can go in Utah — Permanent ADU: residential lots per SB284 and your city's rules. THOW: RV parks, manufactured-home communities, some unincorporated land.
Typical all-in cost — Permanent ADU: from $78,000 + 35–50% site work. THOW: $70,000–$150,000, minimal site work.
Financing — Permanent ADU: HELOC or construction loan (most common). THOW: RV loan.
Effect on property value — Permanent ADU: adds value; homes with ADUs sell 20–35% higher (Freddie Mac). THOW: none — not part of the appraisal.
Where can you actually put each one in Utah?
For a permanent ADU, SB284 sets a statewide floor and your city fills in the details — setbacks, height, size caps, and parking are still local decisions, and two homeowners a mile apart can get different answers. Our Utah ADU tracker keeps city-by-city rules current for 34 Wasatch Front cities.
For a THOW, full-time living is generally limited to licensed RV parks, manufactured-home communities, and rural unincorporated land where zoning permits long-term RV occupancy. Eagle Mountain is the notable exception — it allows tiny homes on wheels in some residential zones. For most Utah addresses, though, the wheels are what keep a tiny home from being a legal residence in your backyard.
Not sure how your lot reads? Tell us your city and lot and we'll tell you what's actually possible — we respond within one business day.
How do financing and resale compare?
A permitted ADU qualifies for real-estate financing. Most of our backyard-ADU buyers use a HELOC or traditional mortgage type financing; construction loans and asset-based loans are also common, and we can introduce you to lender partners. The payoff shows up at resale: research from Freddie Mac found homes with ADUs sell for 20–35% more than comparable homes without one.
A THOW can use a HELOC as well, but traditional mortgage type financing is usually off the table. Instead, a THOW can be financed like a vehicle — typically an RV loan, available on our towable models. Terms are shorter and the unit doesn't appear in your home's appraisal. That's not automatically bad: if you want flexibility, a getaway unit, or housing you can relocate, personal property is the point.
What if you're not sure which one you want?
This is where Cocoon is different: you don't have to decide the legal question before you buy the home. Every Cocoon home is built indoors on our proprietary chassis and arrives towable. From there it has three placement modes — Towable (road-ready on chassis with support jacks), Semi-Permanent (piers, ground jacks, earthquake straps), or Permanent (foundation-set and permitted as an ADU or primary dwelling). Every unit is PE-stamped, and our engineers work directly with your city.
Production takes 10–16 weeks once plans are final, across five floor plans from 170 to 500 square feet. Start towable and convert to a permanent ADU later, or set it on a foundation on day one — the home is the same either way.
ADU vs. tiny home FAQ
Is a tiny home on wheels legal to live in year-round in Utah?
Generally only in licensed RV parks, manufactured-home communities, or unincorporated areas that allow long-term RV occupancy — most cities classify a THOW as an RV, not a dwelling. Eagle Mountain, which allows THOWs in some residential zones, is the main exception.
Does an ADU add more value to my property than a tiny home?
Yes. Freddie Mac research shows homes with ADUs sell for 20–35% more than comparable homes without one. A tiny home on wheels is personal property and doesn't count in your appraisal.
Can the same home be both an ADU and a tiny home?
With Cocoon, yes. Every home is built on a towable chassis with three placement modes — towable, semi-permanent, or foundation-set. Permanently placed and permitted, it's an ADU; on its chassis, it's a tiny home on wheels.
How long does it take to get one?
Production is 10–16 weeks once plans are final. For a permanent ADU, permitting and site work run alongside — budget 35–50% of the home price for site costs.
Ready to talk through your lot?
Schedule a discovery call — no pressure, just straight answers.
Last updated: July 2026 · Cocoon Homes, Lehi, Utah