I recently completed an observation for a homeowner who had discovered vertical cracks in their home’s concrete foundation. The homeowner mentioned he was planning on excavating the soil around the crack and smearing epoxy on the outside of the foundation wall. The homeowner is on the right track however, a more cost effective and better alternative is available. Typically if a hair line crack is discovered in a residential foundation wall and there are not any other signs of movement in the rest of the residence, we would recommend filling the crack with epoxy with a port system. A port system allows the crack to become filled with the epoxy instead of just filling the crack at the surface. The epoxy port system can also be completed on the interior face of the wall so no soil excavating needs to take place. This returns the concrete foundation wall closer to its original state by bonding the concrete together along the crack. In addition, the epoxy also keeps water from intruding into the residence along the crack.
The crack is first cleaned and any loose debris is removed. Next the ports, as seen in the picture, are placed roughly 8” apart along the length of the crack. A paste is then applied over the crack and base of the ports. The epoxy is then injected into each port until it refuses epoxy. After the epoxy hardens, the ports and paste are removed.