The tiny house rocket mass heater: the cyclone batch stylethread has all the information you need to build one, except for the batch box internal dimensions, which you can get from batchrocket.eu. As bricks are generally modular, and 8" long from mortar joint to mortar joint, and 8" tall per three courses, you can use the photos to follow the build accurately. There are lots of photos through the thread, so don't just try to work from the first few posts.
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