Common applications for exterior foundation waterproofing membranes-
Grading Problems: The elevation of the grading around the home is often an issue. Does your home have a sidewalk, patio, or a driveway right next to it? If your patio, for example, is located right next to the house and sits higher than the top of the foundation wall, you could get “over the top seepage”. After a rain or melting snow, water pooling on your patio seeks a lower point and flows next to and over the top of the foundation wall creating the seepage inside. The application of an exterior foundation membrane in that area would eliminate this problem. Exterior membranes can be applied in small, problem areas or around an entire structure, from the footing to the top of the foundation wall.
Porous Foundations: Problems can also be due to the type of foundation wall in your home. Poured concrete walls tend to crack, but each crack can be treated individually. Masonry foundation walls are constructed of brick, concrete block, telephone tile or stone, (all of which can be porous) and all use mortar to bind the pieces together. The mortar is weaker than the masonry units and over time, water will slowly wash away the mortar that holds the wall together. Cracks can also begin to develop due to the weakened mortar and the settling of the foundation. Water will begin to penetrate the mortar and the situation will continue to worsen unless remedied.
To create the waterproof barrier with an exterior membrane for a foundation wall, the earth (and paving, where applicable) next to the wall must be excavated, either by hand or machine. This digging is costly, but necessary to get at the problem. After the wall is prepped and the membrane is applied, the benefits are two-fold in that the seepage will not continue in your basement and the membrane will also help to maintain the structural integrity of your wall.