Cracks are best repaired from the outside, we’ll excavate the area surrounding the crack. Once we excavate it, we take any cracks we find, clean the wall, and chisel 2 to 3 inches on each side of the crack. We then repair it with hydraulic cement and bonding agent. The bonding agent is important because it makes the old concrete adhere to the new. We clean and dry the wall thoroughly, then we put on a thick coat of foundation coating (tar), then we tar the whole thing and wrap it with hydro guard which is a membrane that prevents hydrostatic pressure. While we are down there, we inspect the existing drain tile to ensure it has proper drainage.