I am still in search of a solution to my emergency heat and supplemental heat situation. Just to rehash, I have an old house, and there is not a good place for a wood stove, masonry fireplace or RMH. I have an okay place for a very small RMH, and it may come to that, but a better option is something I could put outside and use to force air inside.
So I found this.
http://www.survivalblog.com/2009/01/how_to_build_an_inexpensive_fo.html
It lacks considerable detail in information, so any thoughts on it would be appreciated, but my other question is this. What about building a larger than usual cob oven, only not insulated and add another "story" to it to capture the heat and insulate all around the entire thing?