In a north facing bedroom, 1900 yellow/London/Cambridge solid brick house, there is damp in the front wall. Below the single glazed sash window, the wall plaster was showing 8 out of 10 on my damp meter. The plaster was falling off, so I managed to pull some off - kicked it hard and it fell on the floor, actually. Took the reading again and the bricks show 0-2 further away from the window, but two bricks closest to the window on each side showed high readings 6-8, the lime mortar between the bricks show higher readings than the bricks it surrounds, all over the section of the wall. After one w