Using Space Blanket in double-layer hammock

[rwsheets]

Has anyone tried using a lightweight space blanket (emergency blanket) in the bottom of a double layer hammock? If so, could you tell that it helped to keep you warm?

[leiavoia]

Space blankets work by reflecting heat and blocking wind. The heat reflection really only works well if there is air between your skin and the space blanket (e.g. wrapped around you). In a hammock sandwich you will not have that because you will be laying right on top of it.

The other issue is that it is a vapor barrier, so all it is really going to do is make you sweaty.

[sidneyhornblower]

Sure. A space blanket is part of Hennessey's Super Shelter, which I and several other folks on here have used successfully. By itself I wouldn't expect much, but using one in addition to a conventional pad or even a blanket or poncho liner will boost the effectiveness. It blocks wind and reflects body heat. As mentioned it can also exhibit condensation.

[Christos x]

I use a heavy duty emergency blanket that ive adapted as an UQ in warmer temps and it works well. Keep it loose but not too loose and it's fine, no sweaty sleepy.
I use it in colder temps between my hammock and Costco UQ, again with no issues.
I'll add my Xped syn 7 in the hammock with minimal inflation when it gets really cold and I'm toasty and snug all night long.

Sent from my E6553 using Tapatalk

[TrailSlug]

As a dead last resort these blankets will keep you alive so if that's the comfort level you are seeking then yes it may work. Just be aware of the condensation that will be present when using one of these.

[cougarmeat]

One YouTube video pointed out that if you have contact with the blanket, you are then dealing with conduction and not radiation - so you want some space. Note that the Hennessy SuperShelter system puts it reflective material under the hammock in a UQP. In mild temperatures that emergency blanket under the hammock in a UQP may work well enough. I used an older therm-a-rest pad for most of a summer before I mored to more exotic ($$$) gear. It worked fine and gave me a go-to-ground option without having to carry anything extra.

[BillyBob58]

It i a complex subject. Since a space blanket(SB), in addition to it's claimed reflective qualities, is also USUALLY a vapor barrier(VB). you might want to look into recent lengthy threads on that subject(i.e. VBs).

I would expect a SB used alone, especially with some slight distance between it and your hammock(which probably would not exist in a double layer hammock's pad pocket), would definitely be better than nothing. (some distance might reduce any condensation from wetting your insulation/clothing.) Certainly worth experimenting with. If nothing else, it will block wind a bit as well a external moisture, and maybe also reflect some radiant heat, and add VB style warmth from possible decreasing evaporative cooling(though not as well as VB clothing). Just blocking evaporative cooling(think swamp coolers and Air conditioners), especially along with a VB's ability to keep the external insulation dry, can add 20+ *F of warmth.

Since the SB will probably also be a VB, and if on the outside of or in your double layer it is probably going to be as cold as the outside air, you are probably going to have some condensation, or a lot. This can cause major issues if not done correctly and adjusted for. But, it will probably still help when compared to nothing. If compare to just letting the cold wind- and possibly splashup or fog or whatever external moisture- just blow directly through breathable hammock fabric to evaporate any moisture from your body. Even if you do get damp from condensation, you might still be better of blocking that wind, radiant heat loss, and evaporation. IMO. I could be wrong, of course.

But the key to using any SB or VB, at least for optimal results and assuming you have some other way of blocking wind and rain(Tarp) is to keep it relatively warm by keeping it pretty close to your skin, with some insulation over it. Since condensation(of evaporated body or clothing moisture, condensing back into liquid) normally happens on a cold surface, keeping t warmer will greatly reduce that problem. So anything that can be placed between the cold air and the SB/VB, will reduce that condensation, as well as keep any moisture from your skin or clothing out of your insulation, vastly increasing warmth. Whole still blocking radiant heat loss and evaporative cooling. Worth experimenting with! But, I would study the theories involved. To avoid soaking your insulation from condensation.