I have a damp chimney breast that had become damp because of the jointing around the stack on the roof. That had been sorted out last year but the breast remained damp. I then had the chimney stack removed about 2 months ago so there is no chance of any water getting in now but the breast remains damp near the ceiling and part of the plaster board ceiling as well. i've checked in the loft and there is no other problems i.e. missing tiles etc.
The fire place was closed off some years ago and has got a vent at the bottom and the chimney is open just below the roof. My damp meter still registers damp and the wall has a slight tint of brown, and you can feel it is slightly damp to touch. can i apply some damp sealant to it so i can repaint it white or is it a case of waiting for a long time before the damp dries out sufficiently