I laid ceramic tile over a concrete slab - new construction. There was a crack in the slab before any tile was laid. I was told by a local tile guy, to use a rubber membrane brushon coating to cover the crack.
I did this as instructed. The specific product I used was called Pro-Red Waterproofing Membrane, "elastomeric waterproofing & anti-fracture membrane". Part of the product description even states, "reduces crack transmission in ceramic tile or stone..."
Everything has been good for about 3 years. A couple of months ago I noticed a cracked tile, and put it on the "to do" list. Last week, it had spread to include 3 tiles total. So I decide that today is the day I will chisel the tiles out, coat the crack with the membrane, and lay new tiles in a day or two.
Imagine my surprise when I begin removing the tiles and discover that they are some of the tiles lying over the already coated crack.
So now I am essentially back to the beginning - sort of. If the membrane didn't stop the tiles from cracking the first time, what would make me think a reapplication will be any different? Based on this, can I expect the tiles along the other
25' of the defect in the slab to likewise crack over time?What can I use to prevent future cracks in the secton of slab that is now exposed? What, if anything, can I do to prevent other tiles that are currently laying on the slab, over the membrane coated fault line, from cracking?
Thanks for any help.