Five years ago we supplied the concrete for an elevated slab that was later covered with vinyl composition floor tiles. We recently got a letter from the building owner telling us that the floor tiles were coming loose and that the flooring installer had inspected the problem, measured the pH at the surface, and found that it exceeded 9. A representative from the manufacturer of the tile and tile adhesive told the installer that the high pH had eaten the adhesive away in 5 years, causing the flooring failure. The manufacturer seems to be placing the blame on our concrete. The building owner contacted us and asked how to treat the concrete so the problem wouldn't recur if the tiles were removed and replaced. What information can we give the owner? More
