Chris Plastow
This sounds suspicious to me! If the wall is wet it could be the following things, roof tiles missing over the too of the wall causing rain water to pool on top of the wall( fit new tiles to that exact area), rain water penetration to the exterior surface ( paint it or spray it with siloxane silicone), rising dampness( inject the base of the wall) all of there's problems are easily identifiable, roof leak, top of wall damp, wall leak, mid wall damp, rising damp, only up to 1.0 m damp.
