We have a 1970s detached house, about 3 years ago in January I noticed as I put the Christmas dec's up in the loft the floor was damp and condensation had appeared on the black material on the loft and was making some of the wood work wet.
When the weather changed it went away .. until next year. Each year I try different things and we get to December and its back. To date I have tried:
1. Covering everything in sheeting so nothing is ruined.
2. Fitting a dozen easy vents and moving them around
3. Moving insulation from the edge of the loft area to increase air flow
4. Resealing the loft door insultation
5. Keeping the heat off in the bathroom and the window open after showers and baths
Im at a loss what I can do to improve the situation and am concerned about any long term damage to the roof, Id be so grateful for the diy drs out there to give some advise please.