I have to say, rocket mass heaters are one of the coolest things I've seen in a while. There's a TON of info on the web and I'm trying to absorb it all, but I have a few questions that I wanted some quick answers to (if possible).
1. Would it be possible to get a permit for something like this in Massachusetts or am I dreaming? Are they legal anywhere in the states?
2. These seem amazing and are not new technology since they've been used in developing countries for a long time which begs the question....why aren't they everywhere?? Am I missing something?
3. Does the thermal mass have to be cob, or could it be something else? I know cob weighs less than concrete/rock/brick, is easy to work with, cheap, great thermal properties, but wondering if anyone has used anything else...
4. Due to their weight, do they have to be built on a ground floor, or could you build one on a first floor with a basement below?
5. let's say the cost of construction wasn't a main concern, how would someone build the ultimate RMH? RMH's are so efficient that, even if you made them with more expensive materials,I would think they'd still be totally cost effective, right?