wind gypsy
WKR
- Joined
- Dec 30, 2014
- Messages
- 9,732
Better safe than sorry for sure. If I was in -60 (which I wouldn’t be) I’d bring legit a hot sack as well (think not garbage bag). I’ve never needed one in any of my bags yet but the coldest camp I’ve been in was -5 F.
Regardless of it being a designed hot sack VBL or a garbage bag, it’s primary purpose is still to prevent moisture from getting trapped in the down.
To be fair they would use a vbl with a breathable shell too at those temps because the moisture in outer edge of insulation would probably start to freeze prior to passing through.