you will not need a vapour barrier if you have used a foilback board, if you do their is a risk of condensation between foil and barrier
Wow Dewey who rattled your cage??????????
I think you can find what you are looking for in the screwfix catouloge.
Make sure all loose flaky paint is wire brushed scraped off and paint two coats,will be ok
I Have used Lafarge board bonding adesive with no problems, make sure you use at least 4 mechanical fixings as well (screws)
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