Two Reasons For Tile Grout Cracking

The most common reason for popped grout is inadequate thinset coverage holding the tile to the floor. First the tile begins to see-saw a little, then the grout bond cracks and starts to come loose. There will usually also be cracked tile, but sometimes the tile remains intact. If the problem is just at a few tiles, you can remove and reinstall or replace just the offending tiles. Cracked grout everywhere means the whole area needs to be redone.

    The second most likely reason for cracked and loose grout is that the floor structure under it was not designed for tile and is flexing because it is not stiff enough. We see this in mobile homes when the homeowner installs tile directly over the plywood floor without a Durock-type backer board. Also, a backer board may be in place but inadequately screwed down or has no thinset beneath it. These two scenarios are more likely to have both cracked tiles and popped grout.

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   Visit our STRUCTURE AND ROOMS page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.