To fix the crack you have a couple of options.
Shower wall tile cracking.
In many cases the crack is not the result of an inferior tile.
You can repair the crack with tile filler and then paint over the filler with a color that matches the rest of the tile.
Simply put because of movement.
It doesn t appear that there has been any movement in the floor or the walls.
Sometimes water has gotten behind your shower causing the shower walls to swell causing cracks in the tiles.
Loss of bond or moving substrate.
Hairline cracks in tile may result from remote obscure reasons such as improperly cured concrete or flexing underlayments and joists.
Fill the hole or crack as best you can.
Broken or cracked shower tiles can allow water and mold to get in your shower walls so they should be replaced or repaired immediately.
In far more instances the crack was caused by anomalies under or around the tile.
In other cases a mastic type of adhesive was used instead of thinset and this can cause the tiles to not adhere the the shower walls and crack.
Tiles generally crack for only two reasons.
Low quality tiles the type and quality of tiles used for your bathroom wall are.
What could be causing the cracking.
There are many reasons why shower tiles can crack and break.
There is a ceramic soap dish in the corner and even it is cracked.
Occasionally a crack along the joint between grout and tile appears to be a crack in the tile s surface.
In this case the substrate might be moving if the studs are spaced farther apart than 16 inches on center allowing that backerboard to flex.
Why does grout crack in the corners of showers backsplashes and against abutting surfaces.
Once you removed it make use of a fine grit sandpaper to brush against it and make it smoother.
Use a putty knife to apply it to the crack in the tile.
Small hairline cracks in ceramic tile showers do not typically allow water to get through.
According to the tile council of north america anywhere a tile surface changes plane like an interior corner or meets an abutting surface against a wall or hardwood floor for example should be considered a movement joint.
Not properly fixed an improper fixing method is one of the main reasons why shower wall tiles crack.
Your shower wall tiles might have cracked due to one of the following reasons outlined below.
You can replace the entire tile.
If your tile s crack seems to run along the tile s outer edge closely inspect the crack to determine if it s really on the tile or just through the grout.