Question

There are several admixtures that can be added to your concrete mix design to minimize the possibility of water penetration through concrete walls. These typically are either a crystalline waterproofing admixture or a pore-blocker admixture. Which one of these is hydrophilic and how does it work?

Answer

The crystalline waterproofing admixture is hydrophilic. When in contact with moisture, the crystals in the admixture are attracted to the moisture and begin to grow and fill the small capillary spaces within the concrete, thus blocking the passage of water. This growth occurs during initial hydration of the concrete and will occur again any time later that moisture penetrates the wall.