Putting a bag in a bag?

imported
#1

I had never thought of this before. What do you think about this: I’ve got a great 0-degree down bag that I will sometimes put a micro fleece liner into (for really cold temps). The liner is supposed to make the bag 10 degrees, or so, warmer.

But I also have a summer weight down bag - rated to 32-degrees. My idea is this: could I forego the fleece liner and put the 32-degree bag into the 0-degree bag? In theory, wouldn’t I have a bag that would go down to -20 (or something like that)?

I do realize that putting one down bag in another down bag would be pointless if the loft of each bag is compressed by the restricted space. But what if there is enough space for the bags and myself? Any other issues you can think of? I guess the extra weight of the 32-degree bag would be a definite, even though it’s only something like 1.5 lbs.

The Unknown Hiker

#2

I attempted something similar to what you are describing here. Last april I went to the whites for an overnight. It was probably down to about 20 degrees that night. I had a 20 degree bag with a 40 degree summer bag inside. I stayed nice and toasty throughout the night. Like you said, the biggest issue would probably be that the two bags would compress some of the loft of one or the other or both.

the unknown hiker

#3

Hey “The unknown hiker”: did I steal your trail name or are you using mine?

The Unknown Hiker

#4

I doubt that you’ll be able to put one inside the other unless they’re radically different sizes without compressing the loft of the inner bag (or of both, but it would probably work out to the same total loss.) You’re best bet for this trick would be to use the 0* bag with the 32* bag zipped open as an overquilt on top. You don’t get much out of the down that’s compressed under you anyway, and it leaves room for both to loft properly. That’d be what I’d try, anyway.

Strategic

#5

Check out big agnes bags, they use a two bag system and it will give you the temp ratings of each bag and then what it will be with the two bags combined. I think the web site is bigagnes.com

fatbackfireman

#6

When I was stationed in Germay, I would put down a ground barrier, place a lightweight bag inside my Army bag and covered up with a poncho. I was soooo toasty warm. It wash 15 degrees and 4 feet of snow outside the tent.

dmarie

#7

Unknown Hiker, this works very well! A while ago I was tenting outside in Northern Maine in the month of January. During the entire month the temperature did not exceed 0 degrees F (not a typo, F, not C). Yes, very cold at night. I had an REI bag, probably a 30 degree bag, not a winter bag. And I had a very old US Army bag as a liner, made of cotton and filled with lumpy feathers. This bag could not have been better than a 40 degree bag. I was fine, no complaints at all! Except when I had to get out the bags…

Brian Osborne

#8

Weight is the real issue.

Conan

Conan

#9

i HAVE THE PERFECT SOLUTION. i HAVE A 40 DEGREE BAG. i MADE A LARGE BAG THAT HAS THE DEMENSIONS OF MY TENT. i MADE THE BAG OUT OF TYVEK. oN REGULAR WARMER NIGHTS i USE THE 40 DEGREE BAG BY ITSELF WITH THE TYVEK AS A GROUND COVER. oN COLD NIGHTS i PUT THE 40 DEGREE BAG INSIDE OF THE TYVEK WARM IS NOT THE WORD. THE TYVEK IS VERY LITE FOR OUT WEIGHT CONSCIOUS FRIENDS. tRY THIS IT WORKS

T BIRD