Crystalline waterproofing is a technology that involves the development of crystals to help achieve watertight concrete structures. Crystalline waterproofing technology is available as a waterproof coating for concrete, or an integral admixture for concrete, for use in both above and below grade applications.

Integral Crystalline Waterproofing (ICW) prevents the movement of water through the concrete by plugging or blocking the natural pores, capillaries and micro cracks, thereby making concrete its own waterproofing barrier. This stands in contrast to more conventional means of waterproofing, which usually involves applying a coating or membrane to the concrete surface. The process is sometimes also attempted through densification of the concrete. The ICW method of concrete waterproofing has been proven effective through successful use in virtually every region in India.