Flat trim moulding is crafted in urethane. As with all our urethane products, flat trim moulding does not need to be primed, as it is factory-primed and ready for finishing. Trim walls, windows, doors, cabinets and more. At Architectural Depot, we offer urethane products ranging from bold and defining to simple and versatile. The non-porous qualities of urethane allow for high performance in both interior and exterior applications. Flat trim is precision molded in rigid urethane foam, one of today's most cost-effective and enduring decorative materials. Flat trim moulding can be installed as wood. It will not warp, crack, decay or offer a food source to insects.