Hi, we have a large front bedroom that we want to split into two for our children to have their own bedroom. The house is a Victorian semi, with no cavity so the walls have an issue with mould on occasion if something is left right up against an outside wall, like furniture etc. I intend to put up a stud wall to split the room, the wall will run perpendicular to the front of the house. My question is should I use something between the wall and the first stud which will be screwed to the wall? Will there be a damp/mould issue if I just screw it to the outside wall?