APP Membrane (Atactic Polypropylene Waterproofing Membrane) is a high-performance bituminous waterproofing sheet reinforced with polyester or fiberglass and modified with APP polymer. It is designed for durable waterproofing and heat resistance in roofs, foundations, basements, balconies, and wet areas. The membrane is torch-applied, forming a seamless, flexible, and UV-resistant waterproof barrier that protects structures from water penetration and weather damage.