Emergency blakent groundsheet

http://www.rei.com/product/804326/therm-a-rest-ridge-rest-solar-sleeping-pad

Same theory. Not sure if it works, just pointing out the similarity.

I use a Emergency blanket as a groundsheet. It works fine for me but you know it is always very important preen/clean the area you are sleeping on. No punctures in my exspensive Neo Air.

From an insulation stand point it makes a lot of sense, I would be a little worried about how fragile it might be though. For Those with experience with them, how bad is it?

What you are asking about is an aluminized mylar sheet. It is a semi-tough sheet of plastic, but it can be easily torn. I'm sure that there is a tiny bit of heat reflected back from its surface, but you will not get much insulative effect. In other words, it is a thin sheet of plastic, and it is not magic.

–B.G.–

I used to use an aluminized ground sheet under my Bibler in snow and real cold situations and I can tell you the effect was noticeable over time in the tent with our perception that we lost less heat through the ensolite pads we slept on. When I stepped up to Thermarest, I kept with the reflecto ground sheet until I stopped camping when it's so cold outside.

Forget that. I'm staying in here. Gimme another shot of that Bailey's for my coffee, man.

Yes, but how much vs the cost and weight. Reflective stuff seems to work best when not quite touching and you can definitely feel the effect. Insulation-wise, they just a thin piece of plastic that is waterproof and windproof. I have used them in a number of combinations and experiments with hammock insulation. I don't think you will get much if any gain directly under your pad, but it may add to the areas immediately around the edge of the pad– the heat reflective properties work only at close distances.

The AMK HeatSheets are polyethylene based and much tougher and MUCH quieter than the original mylar-based space blankets. The AMK would be my first choice if I was going to use one for a ground sheet. I think enough of them to include a HeatSheet bivy bag as part of my emergency backup– every time my feet hit dirt, there is one in my pack.

Like Erik, I think they do add some warmth. On snow they also make a great sled. Which isn't all that compatible with sleeping, however. So I wouldn't use one except under a staked down tent or someplace where the slipperyness won't be a problem.