The outside wall of an upstairs room in a 2 floor terraced house has suffered from condensation. I painted with damp proof which worked for a while, but with the windows shut and heating on the condensation on the wall reappeared. It is not too bad and won’t be an issue in summer.
The more worrying problem is the moudly damp patch that has appeared on the edge of the ceiling plaster & I have moudly patches on the suitcases that I was storing on the top of my cupboards against that wall.
Can I treat this myself? If so, please advise me on what I could get?