A large wet patch has appeared on an outside wall of my house. It is on the first floor, outside the bathroom but there is no sign of damage inside the house (eg on the ceiling below). The bathroom has porcelain tiles on the wall and I don't really want to start taking them off to try to find the source of the water (especially as inside seems okay). Do you think I should try to get a bricklayer to remove some bricks to investigate from the outside? Is this possible? Thanks for your help. Alan
