Hydrow's RMH

So I have an idea I wanted to see if it would work.

I have a drawing (not great but it may help) the piped are not connected because i cant draw them correctly.

Basically the Feed tube and the combustion chamber will be in my garage (heating my work bench area), There is already a hole that leads from he garage to the day-basement (where it is currently used to fill my oil furnace tank) in the picture you can see some 2x12 support beams that hold up the hardwood floors in my living room with a pocket measuring 9'x13'x3' of unused space with 2 crawl space vents in there and 1 outside faucet for watering my plants. I'm wanting to leave a little space on the side where the pipe is (furthest from the garage) so i can fix the pipe if something happens (like last year) and I'm not sure if i should close the vents or not, i do plan on putting in a vapor  barrier between the ground and the cob so it does not soak up the water from the ground and cause steam or other issues. and finally there is an existing chimney that is used on both floors that happens to have an unused  6" duct hole in it. now I'm not stuck to 6" of pipe i could/would use 8" if it would work better.

So if this would work, my other questions would be how deep I should have the pipe in the cob, should I keep the cob from touching the wood frame work so it does not rot it? should i just use cob to fill the area or would having too much cob make it impossible to heat?

Picture & Google Sketch-up files(remove the .txt extention to use) attached

Thanks

how long is the pipe run?
what size system?
what temp range will you want at the exhaust?
where will your clean outs be  and how often will you clean it if its hard to get to?

4 to 6 inches depending on how you want to heat the house the deeper the more mass above the pipe. I usually say 6 inches.
1 Inch of space under the joists. air movement and eliminating hot spots.

test fit and fire the stove outside first so you know you have it all in place, then install it

I have not completely decided how long it will be, I'm shooting for what i have read on here to be the max I should go for 30-40' run.

for the clean outs, where should I have clean outs? the feed tube and combustion chamber will have spots for removal for cleaning but do i need more?

I'd prefer the 6" if it works.

I would put a clean out at each of the elbows so you have access to the straight runs. not cause the systems are dirty but because critters can and will get in the ducting.

Erica has chased out a couple of birds so far and our chimney is about ten feet tall.  the little beggars get in and run through the whole duct system and emerge in the house. no to bad mind you but i sure would not like one to die in the ducting if i couldn't get to it.

About 50' is the max length of duct so far. at 40 to 50' you will want a horizontal exhaust because there wont be much heat left in the gas and vapor it will fall like dry ice fog.