Utah Code § 10-20-623

(1) As used in this section: (a) "Allowable feature" means: (i) a landing or walkout porch that: (A) is no more than 32 square feet in size; and (B) is used for ingress to and egress from the rear of the residential dwelling; or (ii) a window well. (b) "Landing" means an uncovered, above-ground platform, with or without stairs, connected to the rear of a residential dwelling. (c) "Setback" means the required distance between the property line of a lot or parcel and the location where a structure is allowed to be placed under an adopted land use regulation. (d) "Walkout porch" means an uncovered platform that is on the ground and connected to the rear of a residential dwelling. (e) "Window well" means a recess in the ground around a residential dwelling to allow for ingress and egress through a window installed in a basement that is fully or partially below ground. (2) A municipality may not enact or enforce an ordinance, resolution, or policy that prohibits or has the effect of prohibiting an allowable feature within the rear setback of a residential building lot or parcel. (3) Subsection (2) does not apply to a historic district within the municipality.