Sheet-based waterproofing is also known as pre-formed waterproofing. It involves layering a water-tight material over the surface and bonding it. There are multiple thin layers in PWM membranes. The waterproofed materials are layered and bonded together to form a waterproofing membrane. Each of these layers is overlapped by no less than 2″ (two inches) to 4″ (four inches) and is bonded with each other with the help of hot polymer-based adhesives.
