What a basement in-law suite actually includes
A complete basement in-law suite has four parts: a bedroom, a bathroom, some form of kitchen, and a comfortable place to sit. The bedroom must be a legal sleeping room, which under Utah's adopted IRC means at least a 7-foot finished ceiling (R305.1) and a compliant egress opening — a net clear opening of 5.7 square feet, at least 24 inches high and 20 inches wide, with the sill no more than 44 inches off the floor. The bath is usually a full or three-quarter bath. The kitchen ranges from a true kitchenette with sink, counter, and compact appliances to a full kitchen if you're going for a formal accessory dwelling unit. The living space ties it together so the suite feels like a home, not a finished basement with a bed in it. We frame, insulate, drywall, and finish all of it inside your footprint.
Aging-in-place finish touches we can build in
The smartest time to add aging-in-place features is during the finish, not after a fall. Every one of these is a non-structural finish item Wasatch Finish can do as part of the buildout: a zero-threshold or curbless shower so there's nothing to step over; solid blocking (grab-bar backing) framed into the bath and shower walls so grab bars can be mounted anywhere later without finding a stud; 32-to-36-inch clear doorways instead of standard 30-inch doors; lever handles instead of round knobs on doors and faucets; rocker light switches; and generous, layered lighting — recessed cans plus task lighting — because older eyes need roughly twice the light. None of this requires touching the structure. It's framing, blocking, door selection, trim, and fixtures, decided up front and built in once.
What Wasatch Finish does — and the honest scope line
Here's the line, plainly. Wasatch Finish does the interior finish: framing partition walls within the existing footprint, insulation, drywall, paint, trim, doors, flooring, and the finish of the kitchenette and bath. Under our Utah DOPL R101 license, we work non-structurally and keep projects under $50,000. What we do not claim to do ourselves: cutting a new egress window well into the foundation wall, adding a separate exterior entrance, moving or adding an electrical sub-panel, or relocating plumbing stacks and main drain lines. Those are structural or mechanical-electrical-plumbing jobs. We coordinate them with — or refer you to — the appropriate licensed trades (a licensed electrician, plumber, or structural/foundation contractor), then we do the finish around their work. You get one honest finish team, not one team pretending to do everything.
In-law suite vs. legal internal ADU in Utah
There's an important difference between a private in-law suite and a legal rental ADU. Since HB 82 in 2021 (Utah Code 10-9a-530), internal accessory dwelling units — a unit built inside an existing single-family home, like a basement apartment — are a permitted use in most residential zones statewide. But cities can still require owner-occupancy, one extra off-street parking space, and a building permit, and a true ADU typically needs its own kitchen and often a separate exterior entrance. That separate entrance and any new utility separation are the structural and MEP pieces beyond our finish scope. If you just want comfortable space for a parent and won't rent it, you may not need full ADU compliance. Either way, confirm the rules with your city — Highland, Alpine, American Fork, Lehi, Draper, Sandy, and South Jordan each apply HB 82 a little differently — before you design.
Real Utah costs and the radon reality
Finished basement space along the Wasatch Front generally runs about $40–$90 per square foot depending on finish level — flooring, cabinetry, tile, and fixtures move that number more than anything. An added basement bath typically lands around $8,000–$18,000, driven mostly by how far the new plumbing sits from existing lines. Because our R101 license caps projects at $50,000, a full in-law suite is scoped to fit inside that, or the structural and MEP portions are carried by the licensed trades who handle them. One Utah-specific item to plan for: radon. Roughly 52% of Utah County homes tested have come back at or above the mitigation threshold, and Utah has the highest average indoor radon in the country. Since someone will be sleeping down there, test first and budget for a mitigation system if needed — it's cheap insurance for a space built for a loved one.
Bottom line
A Utah basement in-law suite is real finish work — bedroom, bath, kitchenette, and living space with aging-in-place touches — done inside your footprint, while egress wells, separate entrances, sub-panels, and plumbing stacks are handled by the right licensed trades.
Questions
Can you build a mother-in-law suite in a Utah basement without structural work?
Often yes, if your basement already has a compliant egress window and the plumbing can reach the existing stack. In that case the whole project is interior finish — framing within the footprint, insulation, drywall, the bath, a kitchenette, paint, trim, doors, and flooring — which is exactly what Wasatch Finish does under our R101 license. If you need a new egress well cut into the foundation, a separate exterior entrance, or a new sub-panel, those structural and MEP parts are handled by the appropriate licensed trades, and we do the finish around them.
Is a basement in-law suite legal to rent out in Utah?
It can be, but only as a permitted internal accessory dwelling unit under HB 82 (Utah Code 10-9a-530), and the rules vary by city. Statewide, internal ADUs are a permitted use in most residential zones, but your city may require owner-occupancy, an extra off-street parking space, a building permit, and a full kitchen — and sometimes a separate exterior entrance, which is structural work outside our finish scope. A private suite you don't rent has fewer requirements. Always confirm specifics with your city's planning department before designing the suite.
What aging-in-place features can you add when finishing the basement?
We can build in a zero-threshold (curbless) shower, grab-bar blocking framed into the bath walls, 32-to-36-inch wide doorways, lever door and faucet handles, rocker switches, and bright layered lighting — all non-structural finish items decided during the buildout. The key is adding the blocking and wider openings now, while walls are open, so grab bars and a roll-in shower are easy and safe later. These touches add comfort and safety for an aging parent without requiring any change to the home's structure.
How much does a basement mother-in-law suite cost in Utah?
Plan for finished space in the range of about $40–$90 per square foot depending on finish level, plus roughly $8,000–$18,000 for an added bath, with the bath cost driven mostly by how far it sits from existing plumbing. A kitchenette, flooring, tile, and cabinetry choices move the total the most. Because our R101 license caps projects at $50,000, a suite is scoped to fit within that, with any structural or MEP portions carried separately by the licensed trades who perform them. We give you an honest, itemized range up front.
Do I need a permit and radon testing for a basement bedroom in Utah?
Yes on both. A finished basement bedroom requires a city building permit, a compliant egress opening (5.7 sq ft net clear, sill no higher than 44 inches), a 7-foot minimum ceiling, and smoke and CO detectors. On radon, testing is strongly advised because Utah has the highest average indoor radon in the country and about 52% of tested Utah County homes come back at or above the mitigation threshold. Since someone will sleep in the suite, test before you finish and budget for a mitigation system if levels are elevated.