Quote:
'If you use a waterproof layer on the bottom of the bag you will get condensation and then water. If cold enough the water will freeze.

'a waterproof material that has the capacity to be vapor permeable [does not] exist.


I've never had this problem when using a British Army 58 Pattern Down bag. This has a waterproof base built into the bag. Hmm Sounds like Jerry hasn't heard of Goretex or any of the other waterproof MVP materials that other manufacturers such as PHDesigns can provide as an upgrade to their bags.

http://www.ludlowsurvivors.com/sleepingbag.html