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Damp Proofing Question
Constant damp patch in 2nd floor flat
Hope someone can help. I moved into a 2nd floor flat in an old (1900) granite building in Aberdeen this year and have been plagued with a damp problem ever since. There is a large damp patch on the wall of my living room, which extends from about half-way up the wall up to the ceiling. This is an exterior wall to the gable end. Initially we suspected a leak in the roof, but I have had several roofers on the roof and everything looks fine. They have checked the slates and have even re-sealed the chimney caps. The gable end wall also looks to be in good condition. But yet this damp patch remains. I have also checked every bit of the loft above the room, but again can find no sign of any moisture. I have been doing a lot of searching online and the only thing I can now think of is damp caused by something bridging the interior wall to the outside granite wall. Could this be responsible for such a large area of damp? ( about 2m tall by 1m) And if so, how would I go about getting it resolved? Really appreciate any help with this as I do not know where to turn next!
Reading your notes you have said that the roofers have re sealed your chimney caps if the chimney is in the area affected then it could be because there is no air flow venting the interior of the chimney which causes condensation from the soot and comes through the bricks and plaster as damp only guessing without being able to see,or it could be a condensation problem?
good luck regards
Answered 11th Jan 2013
Hi, Unfortunately there is only one real solution to cure the damp , the existing internal wall covering needs removing from affected area plus approx 8 inch , this will no doubt expose the cause as from your explanation it does seem to be bridging from the wall itself . once the wall is exposed you can then seal it with a tanking solution ( any builders merchants should advise and supply )
then depending on thickness either baton out and board using duplex silver backed plasterboard Or if its not possible to use batons fix the board to the wall by use of a decent adhesive ie Gripfill ( as you cant dot and dab duplex board ) then re-plaster and allow to dry thoroughly before attempting re-decoration .
A Decent damp contractor or indeed builder will understand this information ,
Answered 11th Jan 2013