Nothing on this in the key posts, so hopefully someone can advise. I'm looking at putting up roller blinds in my bathroom. The room is fully tiled, and the suppliers say that they want to attach the blinds to the PVC windows rather than the walls, because "tiles can crack". Is this normal, or can they just not be bothered taking care when installing them? Will attaching the blinds to the PVC window cause problems or damage? Thanks!