Have lived in this house 8 years. Finally redoing (full gut) bathroom this July. Just recently we have noticed horizontal cracks in the bathroom tile. Runs almost the entire width of the shower/tub enclosure back wall. We have had issues with crown molding separating ever since we installed a new HVAC system and we are considering adding a humidifier to the system. It appears that the material in the house may be drying out.
The discoloration in the grout is because it was wet. I've never seen grout like this until I moved here. We also have some separation of the back shower wall from the sides. But now that summer is here, and it is more humid, the cracks and separations are less noticeable.
I'm just concerned that this may be an issue with the new bathroom. Any thoughts?
Best Answer
I had a similar problem in my house, and after considerable whining from my SO, I started digging out and replacing the cracked tiles. That turned out to be rather tedious, as the tiles were well attached to the wall and there was much collateral damage.
Ultimately my diagnosis was as Aloysius Defenestrate hints at in the comments. The cracks were along a seam between two backer boards. In my case concrete board below, green board above. The boards where not obviously taped at the seams or supported by any horizontal lath boards between the studs. Either one might have mitigated the problem. Inevitably I ruined the underlying backerboard removing the cracked tiles, but I could see the underlying structure. My repairs involved pre-drilling and toe-screwing some lath boards as support. and layering up new backer, thinset and tiles.