I build as much as I can from what others throw away. I have been using a basic paint can rocket stoves as a portable barbie for years on mountain tops and at sea. In the back yard I have a built in brick basic rocket stove for cooking. A hand full of kindling and the steaks, prawns and fresh fish are cooked in no time!
Now I am researching a stove to heat a large barn conversion in the French Alps. I am very interested in modifying old stoves to make them more effective. The barn already has a great old wood cooker, which has 3 simple air intake ports situated bottom top and middle of the stove. So one can damp down the bottom burn whilst still keeping the temp high in the top of the stove to burn off the gasses.
I am wondering about the feasibility of a secondary add on burner at the chimney stove junction.
I am also interested in the use of thermal mass as we need to heat 24 hrs above the snow line.
Thanks to those organizing this forum I know how much effort this sort of thing takes.