Multifoil Insulation

i used it in my extension roof last year and am not happy with the performance - the room didn't retain the heat very well - wouldn't use it again.
 
There seems to be a significant amount of controversy regarding these types of product: that in practice they do not live up to the claims of the producers.
I think it might be covered more in depth on the Boards.ie website - either in house building or the eco section.

Oops - just read your link.