Yes. Utah Code 10-9a-530 requires most cities to allow one internal accessory apartment in a single-family home as a permitted use. Cities can still require owner-occupancy, one extra parking stall, a registration permit, and long-term (30+ day) rentals only.
Lehi: building permit, roughly $25 internal-apartment application, a dedicated parking stall, owner-occupancy declaration. Saratoga Springs: registration and occupancy permit, separate exterior entrance, one paved stall. Eagle Mountain: one accessory apartment per lot, owner occupies one of the units, separate side or rear entrance. Requirements are being updated across the county in 2026 — we confirm current rules for your address as part of the design.
Four things, typically: a code egress window in the bedroom, a separate entrance (required in most of our cities), a real kitchen, and fire/sound separation between units — plus the city registration. We design all of it in, and your builder files the paperwork.
One-bedroom apartments in the Lehi area rent for roughly $1,300–1,400 a month in 2026. Basement units typically rent near the lower end of that band. At $1,400 a month, a from-$95,000 conversion pays for itself in roughly 6–7 years — and the space keeps adding value to the home either way.