ADU Builder in Utah

In Utah cities and towns, an internal ADU in a detached single-family home that is the owner's primary residence is a permitted use in areas zoned primarily for residential use, with conditions each city or town may set. Under Utah Code 10-21-304, in effect since October 1, 2026, the cities it covers must also adopt rules that permit a detached ADU on a lot of 11,000 square feet or more with a single-family home that is a permitted use there. We confirm the rules for your address first.

Salt Lake City's ADU handbook describes requirements that include owner occupancy on a single-family property. The owner or a family member lives in either the main building or the ADU. The handbook also lists one parking space in addition to existing parking and states that the added space can be waived within 1/4 mile of a transit stop or 1/2 mile of a bike path.

Yes, in a detached single-family home that you occupy as your primary residence. A basement with room for a bathroom, a kitchen, a bedroom, and an entrance can become an internal ADU, subject to the conditions your city or town sets under Utah Code 10-21-303, or your county sets under Utah Code 17-80-303.

Yes, when the garage shares a common wall with a detached single-family home that you occupy as your primary residence. A city or town may require replacement parking when a garage becomes living space. We account for that requirement in the plan.

Yes, where Utah Code 10-21-304 applies. Cities it covers must provide a process for converting a legally built accessory structure into a detached ADU, subject to setbacks and the building, health, and fire codes.

For an internal ADU, Utah's statute covers only a detached single-family home that the owner of record occupies as a primary residence. A city or town may still accept a family member in the owner's place, as Salt Lake City does, according to its ADU handbook. For a detached ADU, Utah Code 10-21-304 lets a city require that the owner live in the house or the unit on the lot. We check the local rule for your address before design.

Yes, as a long-term rental, subject to the conditions your city, town, or county sets. For an internal unit, those can include a rental license, no rentals under 30 consecutive days, and owner occupancy. For a detached unit, a city may prohibit rentals under 90 consecutive days.

Where Utah Code 10-21-304 applies, a city may require no more than two on-site spaces for a detached unit of 650 square feet or larger and no more than one for a smaller unit, plus on-site replacement of the home's required spaces that were inside a converted detached garage.

Yes. Every ADU is built under a building permit from the building office of the city, town, county, or district where the home sits. Cities can add a step of their own, such as West Jordan's ADU application and the ADU permit South Jordan requires for each detached unit.

A habitable living unit created within the existing footprint of a primary owner-occupied single-family dwelling, the definition Utah added to its residential code. A detached unit falls outside that definition and is built to the code for a new dwelling.

Utah's residential code amendments allow return air to move between an internal ADU and the main home, an exception to the rule that keeps return air from one dwelling unit out of another. A shared forced-air system is evaluated during design. Salt Lake City's ADU handbook lists separate heating systems under M1602.2. We confirm the approach with the building office that issues the permit.

Not always. Utah's ADU statutes do not require them. Sunset requires individual meters for a detached ADU before it is occupied. Bountiful, Holladay, and South Jordan do not allow separate utility meters for an ADU. West Jordan City Code 13-5B-8, as Ordinance 26-18 amended it, bars them for an internal ADU and states that separate meters for a detached ADU may be allowed when the utility provider approves them. The city's ADU application lists the bar for every ADU. We confirm the rule with the city before design. Utah's building code does not require the ADU occupant to reach the electrical disconnect serving the unit. Holladay, however, requires the tenant to have unobstructed access to the water and gas shutoffs, the electrical panel, and the HVAC equipment.

Not a one-hour rating when Utah's ADU exemption is met. An ADU whose walls or floor separating it from the home are protected by at least 1/2-inch gypsum board or equivalent on each side of the wall or the bottom of the floor is exempt from the two-family separation requirement.

The schedule depends on the type of unit, its size, the site and utility work, and the building office's plan review. We set it in writing during preconstruction.