We live in a 1940 bungalow with a clay tile foundation. It looks like it's been painted with drylok. The paint is bubbling & peeling in areas. We had a "waterproofing" company in and they recommended the "water guard" system. They said that clay tile can become unstable if excavated from the outside. I have only seen water in the basement once and that was after a horrible rain and we noticed that the gutters needed to be cleaned out because water was running straight down to the edge of the foundation. Is there a proper way to seal clay tile?