Flexible cementitious waterproofing membranes comprise a mix of dry cement and sand, and liquid latex.†The materials are mixed on construction sites resulting in a relatively thin, cementitious liquid that can be applied by brush or roller onto different substrates.
Whilst itís down to the cementitious materials to bring tensile strength, itís the liquid latex that provides flexibility and waterproofing in the system. Flexibility is particularly important in terms of providing bridges over cracks in the substrate. The typical ratio of polymer to cement (based on dry weight) for both products is between 40% and 100% i.e. 80% to 200% liquid latex. Note that increasing polymer content brings more flexibility but a reduction in tensile strength.
Dow Construction Chemicals offers two solutions for production of waterproofing membranes.