We started noticing a damp patch in the corner of our study. All of the walls that have damp/mould are external wall and it is generally in the corner where 2 external walls meet. We were told that the damp/mould was due to the gutters and as they were on their last legs we had the gutters and soffits & facia's replaced at the same time as the windows. It was fine all through the summer but in Oct when we got a cold spell & some rain the damp/mould came back. It has loosened the plaster skim coat which I started to hack off around the isolated area only to find loose plaster approx 0.5m down the wall and 0.5m horizontal across the wall. I am about to repair patch plaster the area but believe that the problem will come back.
I am at an absolute loss. I think it could be condensation but as the room is absolutly freezing without the heating or like a sauna when the heating is on I don't quite know what to do. If I add an air brick then the room will be too cold... Any help would be appreciated as I do not want to replaster and cover up I would like to fix the problem for good.
Ideas and help very much appreciated. Cheers MIKE