This guy has come up with a solution to the problem, of course, he uses three space blankets and a tripod, still, I like it.

I used a double size heatsheet last summer when I fell into our chilly side of Pacific Ocean,probably about 50 something F. water temp. & a sunny but windy day about 75 F.,My teeth were chattering,my camp towel was wet,so the heatsheet was available,& it worked well enough to warm me up in the sunshine,I still had my wet clothes on.I was fortunate enough,that it was summertime,& I had a change of clothes waiting back at camp about 150 yds away,I also ruined the heatsheet on the rocks that I attempted to warm up on,it has holes with duct tape now,I also carry 2 Lg survival bags from Survival resources for now on.no affiliation,just a Happy customer!

I did not watch the whole video or any others. In this video though, even though he appears to be filming in his back yard. And you would hope that the probable cotton flannel shirt, blue jeans and non-breathable rubber boots are not his normal attire for his winter outings...

Survival bags/blankets don't do away with the need for insulation but they do give you a very fast wind / waterproof layer which can be a lifesaver. I always consider it an aid to building a shelter rather than an absolute shelter - although I think anyone who expects to build a shelter from natural materials better assume he has a lot of time / energy / daylight available - my SHTF scenario being injured with night falling relies on getting my butt off the ground and wrapping myself in a survival blanket

In my roughest night out, I found myself foundering in deep (over six feet) snow as night was coming on. I wanted to dig a snow cave, but the dry powdery snow wouldn't support a roof - I used a thin poncho I was carrying and the branches of a handy pine tree to get a roof over my head. No way was I able to get my butt off the snow. I was carrying a stove which enabled me to melt snow and heat water for tea, which is undoubtedly why I survived.

Interesting....This happened in Arizona on the San Francisco Peaks, exactly fifty years ago. I had indeed chosen the longest night of the year to spend the night out....

What I like: Use physics (heat reflection properties of the space blanket plus the fact that hot air rises, so you sit in the upper part of a narrow triangular shape). The chair also gets you off the ground.

What I don't like: Duct-taping together three space blankets is NOT something I want to do in bad weather. I am unsure how good the construction would work in the wind. The construction could be made more wind resistant by adding logs and branches on top of the space blanket, I guess.

Note that the key element is the nice, cheery fire he has built. In cold weather, fire is the key. He would survive, not as comfortably, if he had nothing but the fire. Without the ire, he is only marginally better off.

I can attest to the quality and value of the AMK 2.0 bivy. At least in the northeast, it works as a summer bag, and really adds a lot to late fall camping when you put your sleeping bag in it. As noted, condensation is a problem, so I am also looking forward to the new soon-to-be-available bivy that AMK says deals with the condensation issue.

The HeatSheet blankets and bivys are excellent tools, you just have to understand that they need to be integrated into a system. That system may use natural materials for insulation from the ground. You also have to appreciate that they are ultralight, ultracompact components and it's incorrect to compare them against a wool blanket and down sleeping bag.

These AMK products are far, far better than the old Mylar sheets. Even professional survival curmudgeon Peter Kummerfeldt has become a convert. For years he railed against Mylar blankets, and quite rightly so. But recently he was introduced to the much better AMK versions and he likes them.

The AMK products give you a very light, very compact, and very FAST way to keep wind & water at bay. Combine them with some simple bushcraft and hopefully a fire, and you have a truly useful asset.

The blankets were taped together beforehand. If you used something like gorilla tape, I think the blanket would fail before the tape did. The whole deal looks about softball sized.

He has the bottom sealed with snow, presumably you could use logs or rocks to anchor the bottom, but I do have my doubts how it would hold up in high winds, but then any tarp in high winds is going to have problems. You could gorilla tape in 550 cord loops for anchor points.

Of course, it does depend on found materials and a fire, but its not too bad for something that fits in two coat pockets.

One could rig something comparable with a tarp with a silver reflective side, that would be more durable and easier to anchor, but nowhere as compact. Also, there is no reflector on the fire, which would improve efficiency as well.