Waterproofing Tips: Reinforced Bitumen Membranes Reinforced Bitumen Membrane material is one of the best method of roof waterproofing tasks. But you have to take note, this method must be processed by a professional waterproofing specialists in Singapore. The process of waterproofing using Bitumen Membrane involves laying few of layers of material, usually two or three, across the entire surface of the roof and bonded by hot bitumen, which is then combined with polyester to complete a waterproof membrane. Appling Reinforced Bitumen Membrane material is done in several different ways. Four of the most common Bitumen Membranes methods are.. Pouring and rolling, Torching, Cold adhesive, and