I played a bit with using stick-on velcro buttons to attach mylar emergency blankets to a visqueen tarp set up like a Baker's tent and that works pretty good. I'm sure it'd work with a nylon tarp too. I think you could use a nylon front panel, like I did with the visqueen and it would work just as well, the radiant heat should pass right through it. But with the visqueen you can be sitting inside and watching the fire burn and that's pretty nice.

This Baker's tent is a lot smaller than the one I made with a 10'x10' tarp, but it's still a lot bigger than it needs to be for solo use. I think a smaller one is worth trying out. I also wonder if it'd be worth it to try and glue mylar to a nylon tarp. That 3M spray glue is pretty amazing stuff. Or, you might mix up some silicone solution and wet out the nylon with it then use a squeegee to spread the mylar out over it wrinkle and bubble free. and then let it cure. Either of those laminating processes should make the nylon water resistant. It won't breath anymore though, so the real advantage would be durability. You'll be trading that for weight savings, but my guess is that it'd be worth it. I fully expect the tent I've made to get beat up pretty fast. That plastic is going to get snagged and punctured, I just don't think it's avoidable.

It really is an amazing way to demonstrate radiant heat. You can sit outside right up close to the fire and feel the heat in front of you, but when you get inside the tent and drop that visqueen you feel the heat all around you and it warms you deep inside. If you touch any of the panels they are cool, (even the front panel was cool to the touch) but if you move your hand an inch away you can feel the heat instantly. If you hold your opened hand near the back wall, palm towards the fire, the back of your hand is as warm as the front.

While I'm sure it could be improved, this simple design seems to be very efficient for the purpose. Five of the six surfaces on the tent are reflective and direct the heat inside the tent. The two roof panels reflect it down, towards the floor where it needs it most and the large front surface allows a lot of radiant heat in.

I was going to pack the tent last night but my neighbor called and told me he'd meet me down there to check it out. He was honestly amazed. We built a fire and kept it going for a couple hours and when we had a good bed of coals built up we let the fire die and sat inside for over an hour still getting warmed by the coals (and testing beer ).

We have a chance of rain showers in the forecast tonight so I might leave it up to see how wet it gets inside.

BTW, I want to thank all of your for your interest, suggestions, and encouragement. This has been a fun little project and it's been great to have all of you to bounce it around and learn from. I'm definitely going to keep playing with the concept.

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For the posterity of the thread, I want to point out that here in the Ozarks, when and where I did this, the Fire Weather Risk Level Forecast was "NONE".

I check the risk level here: www.crh.noaa.gov

And I follow all the Federal, State, and local regulations that apply.
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