I found this to be interesting. I did something that was a bit smellier. In a slightly colder situation. I had a canvas tent at about 10 degrees in the cold snow in the fall in Alaska. I strung up ropes from the top corner to top corner and bottom corners. I then used two wool blankets and placed them in the same a frame shape so to create an insulated wall separated from the canvas wall. Then I used a kerosene lamp on low and let it burn all night. It does work and uses little heat. In the future I will intend to make shelters as I have that has a raised platform with a small fire below that (not underneath but beside it) a lot like the Eskimos in their igloos. They would build their beds about a foot higher and place a lighted candle in the lower portion. Heat rises and so with that in mind consider your shelter options. Make the best one available. I was going to post a link to the kind of tent I used but am having difficulty finding the kind of tent. the link will follow when I can find a place that caries them.