Open Terrace leakage work in Manaparai RVs waterproofing construction chemicals Application chemicals supplier distributor What is an APP waterproofing membrane? APP stands for Atactic Polypropylene. APP membrane is the most commonly used waterproofing material on concrete roofs and low-slope roofs. APP membrane is applied to asphalts with a torch. Applications of APP membranes aren’t limited to just roofs. Man made ponds, bathrooms, water tanks, curtain walls, concrete channels can be protected against water ingress with APP waterproofing membrane. APP membrane is a durable waterproofing material largely preferred by contractors for safeguarding surfaces against leakage.