Went to an old cottage last week to fit a shower and shower door. The shower is in an alcove and it had already been tiled, one wall was straight but the other was fairly straight at the top but about 600mm from the bottom it went in about 20mm by the time it reached the tray, too much for the shower wall post to compensate for. I can see 2 options, first take off about 5 rows of tiles and get a plasterer to build it out then retile, second make a fillet out of treated timber seal and paint and insert to build out wall. Any thoughts on these ideas or any other ideas?