Illustration - Vapor Barrier Liners (VBL)

[BillyBob58]

A VBL bag will definitely work. I do have a couple of problems with it. First, it's a bag. I dislike VBL bags for the same reason I choose a TQ over a sleeping bag.
second, I HATE getting out of those things in the morning (or middle of the night) in the cold while I'm wet. VB clothing at least lets me move around under my TQ, and I can swap for dry clothing "one section" at a time come morning.

It is a real kick in the butt, coming out out a VB on a cold morning. That hits a lot harder than coming out of a warm jacket. All of which just demos how well it is working.

[BillyBob58]

......While you're not freezing, you can definitely feel the lack of warmth. With the VB stuff on, I felt no chill whatsoever and felt that I could have gone at least 10 more degrees lower if not more.

Now here's the interesting part. On top of the added warmth, I checked my NS when I got up this morning. You know the way a TQ can feel like it is either damp or cold, but you can't really distinguish which? This morning, the NS felt neither damp nor cool to the touch. It was a dry feeling as when I had it in the house before I took it out. And no frost on the outside of the shell either.....

BINGO! All theories and previous experience confirmed once again! Now for the final test if you feel like it: weight the NS before and after. Then use it in similar temps sans VB and weigh again.

[wisenber]

BINGO! All theories and previous experience confirmed once again! Now for the final test if you feel like it: weight the NS before and after. Then use it in similar temps sans VB and weigh again.

That might take a little bit of doing. First, I'll need to find a few nights in a row with the same temps. Next, the temps should be well below freezing else the NS might absorb moisture from the air. I'll probably need to wear some heavier layers without the VB as the VB seemed to keep me comfy at 21 in the NS.

I'll see what I can manage here in the next few days, but I think we are in for a warmer spell.

[sclittlefield]

Thanks for putting this together. You have such a great knack for simplifying tons of information and putting it together in one easy to understand package. Really nice work!

[BillyBob58]

Yeah, you're right. It would be hard to make a test that was comparing apples to apples. First you have to find two nights with the same temperatures. Plus, you have to have about the same humidity. In addition, just having to add clothes to make up for the lack of a vapor barrier would add another variable right there. Who could say how much moisture the clothing you wore would absorb. But, if you could account for all the variables, it would really be a useful test. If nothing else, if you had zero added weight using the vapor barrier, and then had some added moisture without using the vapor barrier, that would tell you pretty much all you needed to know. Even if the conditions were somewhat different on the two nights of testing.

[MedicineMan]

what you need is a walk in freezer

[wisenber]

what you need is a walk in freezer

...with trees

[Dice]

Any thoughts on these?

They look pretty functional, may not need so many layers, and they seem pretty comfortable! SuperSauna suit... interesting.

[gnome]

CUBEN, make a bag of lite cuben, weighs very little is vapor proof. gnome

[Mat]

When i used to Box i had a sil nyl two peice suit for training (Sauna Suit) and it realy does work, in the winter i would put that on under a fleece and some pants to go running and my sweat didnt soak my clothes, of course i was dripping under the suit but if you only wore it to sleep in i can realy see how it works to increase your bodys micro climate base temperature thus stopping any further sweating.... may have to try and find it now as im intrested to see how it works in the hammock!!!