I am currently working on getting my contractors license in state of Oregon, and thanks to Ernie and Erica people are allowed to legally have rocket mass heaters, at least in portland, I believe. SO... I was wondering about how to do it economically for clients. I have built one in my house, and it took alot of time to make that much cob, I can not make cob for free, and thinking of what the labor would cost the homeowner it seems like it might be just as economical for them to have a masonry heater put in(and easier for them to resell the house with). Just looking for peoples thoughts, especially people that have more experience with cob then I do. (which isnt much)
I would think that you wouldn't make the cob by yourself. Either you would work out an agreement to supply the skilled labor and have the customer make cob, or hire one or two unskilled workers to help you with the grunt work.
Can't cob be made with machines? In europe, we have those "mixers" which fit on the end of telebooms. The way they work, i think, would be good for making cob. You can also make your mass out of other products. It doesn't necessarily need to be cob; And i realy think batch rockets can be way closer to masonry heaters. So there might be several options.
Thermal cob without straw could probably be made by a machine. And for the amount of structural cob needed for a typical bench style RMH, mixing in the straw manually after preparing the last batches of cob would probably not be too difficult. The cost of the right mixer would have to be balanced against how quickly it would pay for itself at various rates of use (how many RMH jobs you would have per year).
Don't MAKE me come back there with this tiny ad:
100th Issue of Permaculture Magazine - now FREE for a while