Porous concrete can be found in both newer and older foundations. Honeycomb concrete, for instance, can form as soon as the concrete is poured. It usually occurs as a result of the concrete being consolidated poorly and is observed by the absence of cement paste between the aggregate or stones. As concrete ages, it can also become soft, causing the surface to erode or crumble. This condition is commonly referred to as spalled concrete.
Addressing the problem from the exterior, or “positive side”, is the most foolproof method to prevent water from seeping through porous concrete. If excavating the wall is not practical or feasible, we offer a number of concrete waterproofing solutions from the interior as well, including our Xypex Process which has proven to be effective in treating small honeycomb areas.
Sometimes it is impractical or undesirable to waterproof a basement from the interior. Common examples include seepage over the top of the foundation or instances where the basement is highly finished. Exterior waterproofing involves addressing the problem from the “positive side” by excavating and applying a membrane to the foundation wall. Depending on the situation, it also may involve adding a perforated drain pipe surrounded with washed stone at the base of the trench to get rid of the excess water.
Potential obstructions such as additions, garages and decks need to be taken into consideration. We can remove items such as concrete, asphalt and pavers. In most instances, digging is done by hand to minimize disruption to landscape.