I hope someone can help.
I have damp at the top corner of a bedroom wall at the most exposed corner of a detached house which, is 10 years old.
The damp appears every morning tere is a heavy frost and doesn't appear when there is rain etc. I have had the roof checked and it appears to be fine, including the roof ventilation.
The 1st time the damp patch was noticed, I discovered that there was no loft insulation in this corner, So I intalled insulation, leaving the vent gap, but the problem has returned.
There does appear to be condensation within the attic, but all the vents appear to be clear.
All extractor hoses appear to be fine and this corner is nowhere near any bathroom extrractor units.
There is a condensdation on all the windows in the house, but only when the heating 1st kicks in.
We had a water leak a view months ago, but de-humidiers were installed on the ground floor to dry out the problem.
Could somebody please tell me what I need to do to resolve this issue?