What offers the best thermal properties? Im after something that will stop the cold and feel lovely and soft, and the plan is to spend more on the underlay than the carpet as its for a kids play room so the carpet will no doubt get replaced sooner than the underlay.

Also, is it worth using something like a foil backed laminate underlay first just to add an extra barrier and bit of warmth?

http://www.carpet-underlay-shop.co.uk/cloud-9-cumulus-pu-carpet-underlay-11mm-19-p.asp

Excellent, i did look at that but wasnt sure if there was something better out there

I have it in three rooms and it’s excellent. The shop have been easy to deal with too.