In Figure A, we see stone or ceramic tile placed directly over a concrete slab. This would be completed after the slab was fully cured and prepared to obtain tile. This signifies that any cracks had been repaired and any floor contaminants eliminated. Common thin-set mortars shrink as they cure, and this displacement of water causes the mortar to retract and pull the tile as it hardens. When this occurs with a thick layer of a common thin-set mortar, it can go away an uneven floor from tile to tile—known as ‘lippage’—or even result in cracking. Mortars with medium-bed options are formulated to regulate the amount of shrinking that happens through the curing process, which allows the tiles to stay degree with one another.

Cracks are sometimes a sign that a wall may be weak and have to be changed. As you have described your installation technique, you’re troweling your …

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