thanks JohnD.
what is this rigid foam? is it same as Knauff space board ? do you have links to this product?
is fibre quilt same as glasswool, i.e space combi roll (http://www.diy.com/diy/jsp/bq/nav/nav.jsp?action=detail&fh_secondid=10186453)?
sorry, this is my first time doing a loft...
I know this question has been asked before, but none of the answers seem definitive.
I want to insulate my loft and still be able to use it for storage.
The current joists are 100mm high X 50mm and I want to increase their height so as to fit in 270mm of insulation and board on top of it...