Negative Side Waterproofing

Negative Side Waterproofing

Many waterproofing methods have been developed to address the task of keeping moisture out of a building’s structure.  However, many of these methods are designed to be placed on the side of the structure that is actually exposed to water, which is usually on the exterior.  In cases where the structure to be waterproofed is underground, this can be a problem.  Waterproofing on the negative side can provide one solution to this dilemma.

Waterproofing on the negative side of a building means that the waterproofing system is placed on the side of a structure where water does not contact it.  In the case of a building, this is usually the interior wall.  The advantage to this is that repairs are easier to access than if the waterproofing was on the positive side.

Compared to positive side waterproofing, the choices for negative side waterproofing are limited.  Usually, the only option available is a cementitious system—that is, a system that is a mix of Portland cement, sand, and a waterproofing agent.  Examples of cementitious systems include metallic systems, crystalline systems, chemical additives, and modified acrylic.   These types of waterproofing can also be used on the positive side of a structure, if that is preferred.