The use of waterproofing admixtures in concrete has often greeted with scepticism, but a new product from Ability Building Colours can provide waterproofing of concrete slabs and structures, even those that are exposed to constant hydrostatic pressure.

Efflorein Mark 2 performance increasing admixture reduces the permeability of concrete to water, water solutions (including chloride solutions) and many other liquids. It can often eliminate the need for additional waterproofing protection such as adhered membranes.

The key to the product’s waterproofing capabilities lies in its ability to significantly reduce the level of macroscopic and microscopic voids within the hardened concrete.

“Untreated, hardened concrete, including high strength concrete, can comprise up to 7-12% (by volume) of permeable airspaces, capillaries and micro-cracks. Under hydrostatic pressure, moisture is forced into the concrete, and these provide the path for water and/or aqueous solutions - including chlorides, sulphates, acids and other chemicals - to penetrate into and through the hardened concrete to adversely affect its performance.” Ability Building Colours' managing director, Robert Barber said.

“By reducing the volume of permeable voids within hardened concrete, Efflorein Mark 2 not only delivers a significant decrease in the hardened concrete’s permeability, thereby providing a positive waterproofing action, it increases the concrete’s compressive strength, which is greater than that achieved by its water reduction action.”