Isbir Construction & Landscape Corp. installed a new driveway, patio, and retaining wall for a client in 2019. In 2020, the client was so happy with the work that he called us back to waterproof the basement wall of his house because of a water problem. He also expressed a concern he had about a horizontal wall crack in his foundation which was caused by this basement wall pushing in.
Our client’s house is about 50 years old and his entire basement is underground. The ground surface outside of his basement wall was sloped toward the house which was contributing to the water problem. While the waterproofing job went off without a hitch, we hoped that once we removed the existing clay soil that was pushing on the foundation wall, that the wall would “relax” and return to its original vertical position. We were fortunate that the wall did return to about 99% to its original position. You can see by the tape in the photo (which was not moved during construction) that the gap was reduced substantially.
The wall was then backfilled with PennDOT certified 2B limestone and it was compacted to create a structural backfill. The compacted and angular backfill locks together when compacted and creates a backfill material that is much stronger than the clay soil that the house was originally backfilled with. This better backfill will reduce the load on the foundation wall. It will also not heave near as much during the winter during deep frost events because the limestone allows water to pass through it, rather than retain the water.