General Contractor in Alpine, Utah

Ordinance 2026-16, adopted September 8, 2026, amended Sections 3.14.010 and 3.14.020 of the Alpine Development Code and added Section 3.14.030 for detached ADUs. Both internal and detached units need an ADU permit from the Building Department, in addition to any building permits, and a registration and rental license renewal form filed with the city each year.

For an internal ADU, Section 3.14.020 sets conditions that include these.

• A zone in which the code lists accessory dwelling units as a permitted use
• An owner-occupied single-unit detached home, unless an owner who has lived there for at least a year files a temporary absence application before leaving, for a bona fide absence of three years or less on an activity such as a temporary work assignment, sabbatical, military service, or voluntary service; or for a stay in a hospital, nursing home, assisted living facility, or similar facility
• No renting or offering the internal unit for rent while a detached ADU on the same lot is rented or offered for rent
• At least four off-street parking spaces for the home, garage and driveway included, with at least one designated for the ADU
• No rental, or offer to rent, for less than 90 consecutive days
• At least one separate outside entrance, on the side or rear of the main home
• No more than one meter for each water, gas, and electric service, in the owner's name

For a detached ADU, Section 3.14.030 adds conditions that include these.

• A zone where single-family dwellings are a permitted use
• Living area of at least 300 square feet, and no more than 800 square feet on a lot of less than 10,000 square feet, 900 on a lot of 10,001 to 20,000, 1,000 on a lot of 20,001 to 40,000, and 1,200 on a larger lot
• An owner-occupied unit, or a property with an owner-occupied single-family home, under the same temporary absence terms
• Permanent structures covering no more than 35 percent of a lot of less than 10,000 square feet, 30 percent of a lot of 10,001 to 20,000, 25 percent of a lot of 20,001 to 40,000, and 22 percent of a larger lot
• No renting or offering the detached unit for rent while an attached ADU on the same lot is rented or offered for rent
• Occupancy by one individual or by a family as Section 3.01.110 defines it
• A rental minimum of 90 consecutive days, with no offer of a shorter rental
• One on-site parking space beyond the home's for a unit of 650 square feet or less, and two for a larger one
• The setbacks the zone requires for accessory buildings
• The zone's accessory building height, and never more than 25 feet to the top of the roof ridgeline
• A design consistent with the main home's
• A connection to the main home's meter for each water, gas, and electric service, in the owner's name, with no unit allowed where the meter lacks the capacity
• Conversion of a legally built accessory structure through the city's process, under the accessory structure setbacks and the building, health, and fire codes

The City Council's motion adopting Ordinance 2026-16 holds a detached ADU to the lesser of its living area limit and the lot coverage limit. Utah's ADU statutes apply in Alpine as well, as our ADU page explains.

Sources: Development Code Section 3.14.020; Section 3.14.030; City Council Minutes, September 8, 2026; Utah Code 10-21-303. We confirm the rules for your property during preconstruction.

Utah ADU Law and Building Code