What could be causing cracks to appear in ceramic floor tiles?
There is always a remote possibility of an individual fractured tile, usually caused by not being bonded properly and then being impacted by an object dropping o n it. That type of fracture is repaired by replacing the damaged tile. A sure rule of thumb to determining the problem: if the crack goes from one tile to another on a continuous line through the grout joint, the problem, without any doubt, is in the substrate; usually a crack in the slab. The damaged tile would have to be removed, a crack isolation membrane put down and the tile reinstalled; which should solve the problem.
