View Full Version : Space Age Emergency Blanket
In the never ending search for smaller and lighter, has anyone tried using a "space aged emergency blanket" for wind break/warmth between sleeping bag and hammock, rather than under quilt? I am not a hanger (yet), but ready to try. AT in NC in mid-Sep, so probably not below 50 F.
Too much noise (crinkly)?
Transfers cold?
chiefduffy
07-30-2014, 21:23
There is very little insulating capacity in a space blanket. It has been tried. Nice idea, tho. Many hammockers use Garlington Insulators or PLUQs in warmer weather instead of a pad. Check out HammockForums.net for more information.
Wise Old Owl
07-30-2014, 22:04
there are several threads stored here basically its a boy scout fail. Your gear will support you. The product clearly works for several hours and then dumps lots of perspiration right on you as the temp and humidity changes. That's the short answer.
mudsocks
07-30-2014, 22:48
Like others have said they trap sweat and condensation. I also suspect they will not hold up to long term use.
Coated Mylar "space blankets" are reflectors - not insulators. They work very well to reflect radiated heat back to its source - up to 90% it is claimed. So to use one effectively, put it between your sleeping bag/quilt and your sleeping pad, with the reflective side toward you. The blanket should not touch your skin. It works great to improve the r value if your insulation.
They can also be used as wind breaks and to reflect back the heat of a campfire. Great to have in an emergency. You can use them to build a shelter to stay dry. They weigh next to nothing.
They don't last long though - the reflective coating scrapes off and they become wrinkled. They are incredibly cheap though so this is not a barrier. They are also noisy and generate a ton of static electricity.
Condensation would be my biggest concern and I don't expect there would be any insulative value to it. You might benefit from hanging it loosely under an UQ on wet evenings, but even then I would be worried about condensation..
I've seen twice CHEAP SUL not very durable though DIY mylar space blankets made into under quilts. As Magneto said it's their reflective and prevention of heat loss through convection that can help a ground dweller and hanger.
I've never made such an UQ for hanging but will consider throwing one into the sleep mix as a groundling using as a ground sheet and more rarely as top layer in ground situations. The cost, simplicity, versatility, and low bulk makes it attractive to consider IMO for me. For inside a sleeping bag in winter they can act as a VBL suit but perhaps as a cheaper lighter wt alternative. There are crinkly and not very stealthy in color or sound though.
I've seen twice CHEAP SUL SOL Emergency bivies, not very durable though, DIY mylar space blankets made into under quilts. As Magneto said it's their reflective and prevention of heat loss through convection that can help a ground dweller and hanger.
I've never made such an UQ for hanging but will consider throwing a mylar sheet one into the sleep mix as a groundling using as a ground sheet and more rarely as top layer in ground situations. The cost, simplicity, versatility, and low bulk makes it attractive to consider IMO for me. For inside a sleeping bag in winter a mylar layer can act as as non permeable vapor barrier or the SOL Emergency Bivy can act as a VBL suit but perhaps as a cheaper lighter wt alternative. They are crinkly and not very stealthy in color or sound though. The SOL Emergeny Bivy, I think a woven outer material(whatever it is), starts to pill after a while.
I've used them for a quick ground cover to sit on especially if the ground is moist. Also helps to spot ticks or other crawlers before they get to you. Used it as a wind block inside my tent on an unusually cold windy night. Works well, but does not last long. Light and cheap so I usually carry one.
ScareBear
12-15-2016, 05:13
In the never ending search for smaller and lighter, has anyone tried using a "space aged emergency blanket" for wind break/warmth between sleeping bag and hammock, rather than under quilt? I am not a hanger (yet), but ready to try. AT in NC in mid-Sep, so probably not below 50 F.
Too much noise (crinkly)?
Transfers cold?
It is simply a piece of mylar plastic film coated with a reflective "paint". There is a reason they are very inexpensive....
I have used them on snow before sitting and they do work a bit. They are best as a Vapor Barrier Liner(VBL) when you have lost control of the temp v. bag rating battle and things have gone way South. Then, deploy the blanket INSIDE your bag with the blanket surrounding you. You will be a little wet. But you will be warm and alive in the morning. The whole idea of the VBL is to eliminate the effect of evaporative cooling(perspiration) by eliminating the evaporation part by trapping the output of your engine(heat and moisture) and using it to keep you warm in an emergency situation. Completely effective at blocking the wind. SOL makes a host of great products, from an inexpensive mylar bivvy sack to go in or over your bag to a fairly expensive(40 bucks) woven, breathable(kinda, mostly by venting) bivvy. I actually use that as part of my summer sleep system along with a synth/silk liner...YMMV...
All that said, theoretically, it should work in a hammock. It will stop all wind. It will stop almost all heat transfer from the bottom of the bag to the atmosphere. I don't know how much heat it will "reflect" back into the bag...I suspect not much...YMMV...there are threads on WB about hammocks and liners...