Does my lot qualify for a detached ADU?

If it's 11,000 square feet or larger, already has a single-family home on it, and sits in a zone where single-family homes are permitted, your city has to allow one after October 1, 2026. Below that size it's entirely up to your city. Lot size is on the county parcel record, so this is a lookup — send us your address and we'll tell you, at no charge.

Is a detached ADU cheaper than finishing my basement?

No, and usually not close. A detached unit needs a foundation, roof, exterior walls, and a utility run — all of which your basement already has. For similar rent, the basement is typically the far better return. We build both, so we have no reason to steer you either way.

Can my city still make me get a conditional use permit?

Not for a unit that qualifies under the state threshold. That was the biggest practical change in SB 284: a qualifying detached ADU is a permitted use, so it can't be sent to a hearing where neighbors object. Cities keep authority over setbacks, height, design, and parking.

Your city can't cap the size outright, but it can require the unit to be smaller than your main house. Setbacks and lot coverage limits usually end up being the real constraint — plenty of qualifying lots have less buildable area than the owner expects once those are applied.

Can I rent it on Airbnb?

Often no. Several cities in this corridor specifically prohibit short-term rentals in an accessory dwelling unit, and it's one of the most common conditions attached to the new ordinances. If short-term rental is the whole reason for the project, confirm it before you spend anything on design.

Do I have to live on the property?

In most cities here, yes — the owner has to occupy either the main house or the unit, and some cities record that as an affidavit against the property. It's the requirement that most often stops an investor buying a house purely to rent both halves.

A second home on your lot — where the lot and the ordinance allow it.

Detached ADUs & Backyard Cottages

A standalone unit in the backyard: its own foundation, roof, kitchen, and address. Utah law now requires most cities to permit one on lots of 11,000 square feet or more. It's the more expensive of the two ways to add a rental, and sometimes it's the right one.

Typical investment: $190–$350 per square foot
Timeline: Typically 5–8 months from feasibility to certificate of occupancy, with zoning and utility approvals accounting for a meaningful share of it.

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What changed, and why you should ask again

Utah's SB 284 takes effect October 1, 2026. Cities over 5,000 people have to permit a detached accessory dwelling unit on any lot of 11,000 square feet or more that already has a single-family home on it, in zones where single-family homes are allowed — and they can't require a conditional use permit for one that qualifies. That last part matters more than it sounds. The conditional use hearing was where a neighbor's objection could end a project.

Cities across Utah County are rewriting their ordinances on that deadline right now, and several hadn't finished when we last checked. If your city told you no before, that answer may be out of date. We track where all nine stand, with sources, on our ADU rules page.

The honest comparison, which usually favors your basement

A detached unit and a basement apartment rent for broadly similar money in this county. They do not cost similar money to build. The basement already has a foundation, a roof, exterior walls, and utilities at the building — the detached unit needs all four from scratch, plus site work.

So the cost per rentable square foot is dramatically different, and for most homeowners asking us about a backyard cottage, finishing the basement is the better financial decision. We say that plainly because we build both and get paid either way. An honest comparison from someone with no stake in the answer is worth more to you than a brochure.

There are real cases where detached wins: the basement is already finished or already occupied, the house has no basement, you want the tenant fully separated from your household, or you're planning for a parent who needs single-level living with their own front door. Those are good reasons, and when they apply we'll build it.

What actually decides whether you can build one

Four things, in order. Lot size, because 11,000 square feet is the state threshold and it's a matter of public record rather than opinion. Zoning, because the guarantee only applies where single-family homes are already permitted. Setbacks and lot coverage, which is where a qualifying lot can still turn out to have nowhere legal to put the building. And utilities — specifically whether sewer can be reached by gravity, because a lift station is a cost and a maintenance obligation people don't anticipate.

We check all four before anyone pays for a design. It's a lookup and a site visit, not a project, and it's free.

What's included

Lot, zoning, and setback feasibility check before any design work
Site plan and unit design, with our designer
Foundation, framing, roofing, siding, and windows
Complete kitchen and bathroom
Utility connections — water, sewer, power, and gas where applicable
Separate electrical service or subpanel, with submetering where you want it
Full permitted construction through certificate of occupancy
Site restoration, grading, and drainage away from both structures

What the process looks like

Feasibility first, and free. Lot size against the 11,000 square foot threshold, your zone, your city's current ordinance, setbacks, and where the sewer sits. This is the hour that decides whether there's a project at all.
The comparison. Before design, a straight side-by-side against finishing or converting your basement — build cost, rentable square feet, and what each one does to your yard. Sometimes this ends the conversation, which is fine.
Design and site plan. Layout, elevations, and placement on the lot. Placement is the decision that's hardest to undo, so it gets the most attention.
Permits and utility approvals. Building permit, zoning sign-off, and the utility connections. Utility approvals are usually the long pole and we start them early rather than in sequence.
Build and inspect. Foundation through final, with the same standards we hold below grade. Inspections at each stage, scheduled and met by us.

Frequently asked questions

Does my lot qualify for a detached ADU?: If it's 11,000 square feet or larger, already has a single-family home on it, and sits in a zone where single-family homes are permitted, your city has to allow one after October 1, 2026. Below that size it's entirely up to your city. Lot size is on the county parcel record, so this is a lookup — send us your address and we'll tell you, at no charge.
Is a detached ADU cheaper than finishing my basement?: No, and usually not close. A detached unit needs a foundation, roof, exterior walls, and a utility run — all of which your basement already has. For similar rent, the basement is typically the far better return. We build both, so we have no reason to steer you either way.
Can my city still make me get a conditional use permit?: Not for a unit that qualifies under the state threshold. That was the biggest practical change in SB 284: a qualifying detached ADU is a permitted use, so it can't be sent to a hearing where neighbors object. Cities keep authority over setbacks, height, design, and parking.
How big can it be?: Your city can't cap the size outright, but it can require the unit to be smaller than your main house. Setbacks and lot coverage limits usually end up being the real constraint — plenty of qualifying lots have less buildable area than the owner expects once those are applied.
Can I rent it on Airbnb?: Often no. Several cities in this corridor specifically prohibit short-term rentals in an accessory dwelling unit, and it's one of the most common conditions attached to the new ordinances. If short-term rental is the whole reason for the project, confirm it before you spend anything on design.
Do I have to live on the property?: In most cities here, yes — the owner has to occupy either the main house or the unit, and some cities record that as an affidavit against the property. It's the requirement that most often stops an investor buying a house purely to rent both halves.

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Ready to talk about your project?

Get a real number you can plan around — no appointment needed to find out roughly what your project costs, and no pressure when you do.

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Pricing Published Up Front
Orem to Lehi
One Point of Contact