Hi I have been looking at the posts regarding boarding out lofts and have a question. I plan to use the chipboard type floorboards to cover 70% of my loft. At the moment the full loft has 100mm insulation and no vapor barrier. if I put the boards down it will compress the insulation slightly (the gap between the ceiling and the top of the wood is around 80mm. The roof has no felt so the cement from the back of the tiles is all over the insulation.
As I am not boarding out the entire loft do I need to put a vapor barrier down?
How do I know weather the insulation needs replacing?
Cheers
K.J