We have a shower that has walls on 3 sides and a door on the 4th side. One of the sides is a tiled wall but the rear and other side are both tiles over sheets of plywood. Needless to say, water has got behind the tiles on one side and the wood warped badly. This has now been repaired using a sheet of laconite (?) in place of the wood and this has been tiled over. However, the rear of the shower is now leaking and removing the tiles (Which just fell off...) reveals soaking plywood and a damp. musty smell. For some reason, this wood is about 5-6 inches clear of the wall that is behind it, I guess it's to allow room for the shower unit. Problem is how do we remove the rotten wood and what do we replace it with? Does this sound like a complete retile job? Hopefully not as the complete bathroom is tiled from floor to ceiling.