cracked tiles from floor up to roof

[spenny]

hi,
just been out to price a job for a bathroom that about 10+ years old and has recently developed cracked tiles from the bottom of the shower tray, almost in a straight line going up towards the floor.
What do you reccomend best to do? I thought removing all tiles and putting up new ply for the full wall? I cannot see any obvious subsidence in the room,and the other side of the wall (in the other room) appears absolutely fine. Anyone had any experience of this happening,or should wacking up new ply sort the problem?

[cornish_crofter]

The problem is that you don't know why this has happened until you remove the tiles and see what's underneath.

It's possible that you've got two separate substrates, masonery and plasterboard for example. There are several options for coping with this. Assuming that the building isn't suffering from subsidence I would have thought that making sure it's all one substrate would prevent this in the future.