From the post with the title "Between-floor insulation" there is a link to

http://www.screwfix.com/search.do;jsessionid=1TKB24B535ZJYCSTHZPCFFA?_dync harset=UTF-8&fh_search=foil+tec

It says in the review that it encourages heat to rise. Can someone tell me
what I am missing out on here as I thought heat did rise.

Adam