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Planning estimate · Bountiful, Utah

ADU remodeling cost calculator

For a unit that already exists. Tick what actually needs doing and the estimate splits into three: what the code requires, what the rooms cost, and what is there for comfort. Only one of those three is optional.

A planning estimate, not a contractor quote. Nothing you enter is sent anywhere.

Refresh · Legalise · Full gutNothing is assumed
Your estimate

What is behind the number

Read this before you use the number

This is a planning estimate, not a contractor quote. It is built from Utah’s own accessory dwelling unit statute, from Bountiful’s published ADU requirements, and from current Wasatch Front ADU cost data. It cannot see your ceiling height, what your lot does at the back, what the panel can carry, or what is behind the basement wall — and those are the things a real price turns on. Impact fee figures are allowances: Bountiful publishes its own schedule, and it is worth confirming the current numbers with Planning on 801-298-6190 before you budget.

What drives the price

What decides the price of an ADU remodel

This calculator prices work on a unit that is already there. That includes the most common ADU job in this valley, which is not a remodel at all in the usual sense: bringing an existing, unpermitted basement apartment up to standard and onto the record.

The reason it is worth its own tool is that the money goes somewhere people do not expect. On a legalisation the largest share is usually code and compliance — egress windows, fire separation, electrical, and the drawings and inspections to get it recorded — rather than the kitchen, which is the part you can see. So the estimate here is split three ways rather than given as one number.

Nothing is assumed. Tick nothing and the calculator shows an em-dash rather than inventing a scope, because a remodel estimate built on guesses is worse than no estimate at all.

Whether it is being legalised

An unpermitted unit needs egress, separation, electrical and an as-built drawing set before it needs a new worktop. Getting it on the record is also what makes it insurable, financeable and saleable, which is usually the real reason to do it.

Egress

Bedrooms need a way out. On a basement unit that means cutting the foundation wall and building a well, and it is the single item unpermitted units are most often missing. It is not negotiable and it is not cheap.

How far you open it up

Cosmetic, some walls open, or back to the studs. A gut costs about a third more and it buys certainty — on a space last finished decades ago that can be worth more than it costs.

The age of the finish

What was normal when it was built is what you find when you open it. A basement finished in the 1970s was rarely intended to be a separate dwelling, and it shows in the wiring, the insulation and the head heights.

How material gets in and out

A basement unit is reached down a staircase, and every sheet of plasterboard and every cabinet goes that way — as does everything that comes out. A tight or winding stair costs real money across a whole job.

What is code and what is choice

The split matters more than the total. If the budget is tight, the honest order is the code work now and the kitchen next year — not the reverse, which is how a good-looking unit fails an inspection.

What pushes it higher

  • Bringing an unpermitted unit onto the record.
  • Egress windows, which mean cutting the foundation wall and building a well.
  • Going back to the studs rather than opening only what needs opening.
  • An older space, where more of what you find needs doing.
  • A tight or winding staircase, which every sheet of material has to come down.
  • A high-end finish level.

What brings it down

  • Doing the code items now and the finishes later.
  • Keeping the kitchen and bathroom where they already are.
  • A cosmetic refresh where the structure and services are sound.
  • A walkout or ground-level door, so material comes in at grade.
  • A standard finish rather than an upgraded one.
  • Finding out what is behind the wall before committing to a scope.

Turn the estimate into a real number

Send a description of the property, roughly what you are picturing, and who the space is for. Every plan starts with your lot — the ceiling height, the fall of the ground and what the services can carry decide more than the floor plan does.

Questions

What people ask about this

I have a basement apartment that was never permitted. What now?

It is a common situation and a fixable one. The work is usually egress for the bedrooms, fire separation between the units, electrical brought up to standard, and an as-built drawing set the city can review against. Bountiful approves internal ADUs at staff level, so the path is a good deal shorter than for a new detached unit.

Why bother legalising it?

Because an unpermitted unit is harder to insure, harder to finance and harder to sell, and because a unit that fails on egress is a genuine safety problem rather than a paperwork one. It also has to satisfy the same basic conditions as any Bountiful ADU: one per property, the owner living in one of the two, and not renting both.

Does remodeling an existing unit trigger impact fees?

No. Impact fees attach to new dwellings. An existing unit is not one, and an internal unit would be exempt in any case under Utah's internal ADU statute.

How much of a legalisation is code work?

On a typical scope, a little under half — and that is the half you cannot skip. The rest is rooms and finishes, where the choices are. This calculator shows the split explicitly for exactly that reason.

What is an egress window and why does it cost so much?

A window big enough and low enough to climb out of in a fire, which on a basement means cutting through the foundation wall and building a lined well outside it, with drainage. It is structural work, not glazing work, and it is required for any bedroom.

Should I gut it or work around what is there?

If the existing work is sound, a partial scope is genuinely better value. If two previous owners have each had a go at it, a gut is usually cheaper than three surprises. The honest test is whether anybody knows what is behind the walls.

Can I do the code work now and the kitchen later?

Yes, and it is often the right order. The code items are what make the unit legal and safe to live in; the kitchen is what makes it pleasant. Doing them the other way round is how people end up with a smart unit that cannot be rented.

Is this a quote?

No. It is a planning estimate. On an existing unit the biggest unknown is what is behind the finishes, which is why the contingency here rises when a unit is being brought onto the record.

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