Hi folks, After buying a 1920s house last summer I'm sure this won't be the last question I pose... We were aware the rear bedroom had some lingering signs of damp (was also picked up in our survey) - my builder has sealed the external wall that was the cause, but the damage has already been done to wallpaper inside. The old glue has seeped through and made a very sticky mess underneath. No problem in taking this off, but the wall is rather peculiar... it's not brick, there's another layer over the top of it. Tapping it confirms this. What's the best thing to make the wall good again? Cheers! Matt