WUI (Wildland-Urban Interface) zones in Utah’s foothill communities — portions of Sandy, Draper, Cottonwood Heights, and Salt Lake City above the valley floor — may require deck and overhead structure materials to use Class A fire-rated or ignition-resistant construction per local code or fire marshal requirements. In WUI-designated zones, composite and cellular PVC decking are the appropriate material specifications: both have higher ignition temperatures and lower combustibility than natural wood. Some Utah WUI municipalities require fire marshal review as part of the deck permit process. RainFire Builders verifies WUI designation status for every foothill community project and confirms material specifications against applicable requirements before design is finalized — not after the permit is submitted.