CWS InSeal


Internal Spray Applied Waterproofing

CWS InSeal is a concrete waterproofing material, based on the family of sodium silicates. It is applied by spraying onto cured concrete. It waterproofs and protects the concrete from corrosion and chloride/sulphate penetration, by forming a waterproof insoluble gel layer in the concrete matrix, reacting with calcium and water. CWS InSeal will seal static cracks in the concrete and is for use predominantly in indoor areas of low thermal stress.

Why use CWS InSeal?


Apply CWS InSeal with a backpack sprayer (low pressure sprayer), or a motorised pump, depending on the size of the surface to be treated

Super-Fast Application

One person with a backpack sprayer can apply 1000m2 per day and with a motorised pump can apply about 6000m2 per day. Compare this to a membrane where one person can typically apply no more than 100m2 per day


The dosage is around 1lt/5m2, depending on the MPa and surface finish of the concrete. In cases of high MPa concretes, where the surface is finished to a smooth result, proper application may only be 1lt/6m2 whilst, low MPa concretes with rougher finish and open pores, may use about 1lt/4m2

Environmentally Friendly Earn LEED Points​

CWS InSeal products are the most environmentally friendly in the world. Accordingly, we were are members of the

prestigious US Green Building Council (USGBC). The USGBC is responsible for the LEED program.