This spring, I've been slowly working through the "The Rocket Mass Heater" book by Erica and Ernie Wisner because I'm interested in building a stove to heat my home. From what I've read in the book and a few other on-line sources, indicates that a rocket mass heater functions best when located directly in the living space of the home. The physical layout of my home does not allow for this. I have been heating my home for over 20 years with a basic down-drafter wood stove located in the unfinished basement of our house. The heat from the basement passively maintains the entire house at a comfortable temperature throughout the winter (1600ft^2, ~5 cords). We live in the mountains of northern Vermont and -25F or lower is not at all uncommon. The basement has plenty of space to accommodate a rocket stove with a thermal mass structure typical of what the book designs show. What I'd like some input on is whether locating the rocket stove there would be able to heat the entire house as we are currently doing with the wood stove. Does anyone have a similar setup? I'm really liking what I read about having a cleaner burning stove and more efficient heating in general, if this will work.
Hi Mark; Big Welcome to Permies! And another big welcome to the wonderful world of Rocket science!
I added your post to the rmh forum for you.
Normally we do not recommend placing a RMH in a basement.
A J tube design like your reading about in the builders guide would require feeding every 45 minutes or so.
While it was burning your home would be comfy. At night however , (at below zero) with no fire. Only the basement would gain from the radiant heat.
There are options) To start, in your location I would suggest building a batch box design RMH.
You will not find much info about them in the builders guide.
Here is a link to the best technical information available about them. http://batchrocket.eu/en/ Here is another link to a batchbox builders forum. https://donkey32.proboards.com/ We also have info here at permies... I suggest lot's of reading for you... you will be impressed!
A batch box burns even hotter that a traditional J tube and it burns longer as well.
Wood is larger and loaded horizontal.The stove burns wide open. In well insulated homes , batch boxs are generally burned only in the morning and evening.
During your arctic freezes you would burn it more.
With a batch box you have the option of not using a horizontal piped mass, but you can build a vertical brick bell. They can made to fit in any odd areas that your living area has available.
Maybe you might have a spot in your living area where a tall skinny brick bell could be built ?
Extra floor support is generally not needed with a bell.
EDIT) A J tube RMH can be built with a bell also.
For all your Rocket Mass heater parts.
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I'll be building my RBMH in my basement as well. Just no good place for it on the main floor. I'll be going with a bell for the mass, and connecting to an existing masonry chimney that I will line with stove pipe and insulate. I had planed on building it last summer but building a chain link fence to make sure my dogs and property were safe took priority - damn that's some serious work there. Digging post holes isn't my idea of fun.
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