Trickle vents versus air vent through the wall I have mould on inside walls that face north so get no sun. I am told the brick used is not thermal so the wall inside the cavity sweats and the inside then gets damp. Has been suggested that the plaster needs to be removed as mould will still live in it , then either trickle vents in windows which can be left open I live on a ground floor flat or have air vents put through wall although have been told this will make it worse as will be to cold. Also suggested maybe using thermal wallpaper. What would you say ?