Have a fold up sheep herder stove that heats a 12 x 14 wall tent with temps down into the -20's. Light weight material and it throws out heat within minutes of lighting. So far, we have about 30 seasons out of it. Super for horse packing, as it's about the size of maybe two encyclopedias. Have been in camps with much heavier units, and it takes 15 to 20 minutes for those to heat up and start emitting warmth. Actually, with a lantern, the stove, and a couple cooking burners running, we usually need to open the doors to get things down to a reasonable temp.
Can't find a xerox copy, but the following link has some close approximations. L
Fold Up Stoves Link
