Position of an rmh in a house

My sister is planing a dodecagon cordwood hous that will be about 45 ft in diameter, 1600 sq ft space, heated with a rmh. My question is: with an open floor plan, would a standard j tube rmg with a bench against the outer wall heat bedrooms on the opposite side of the house? They are planning an earthen roof and would like to avoid punching a chimney through the center of it… photi of a tentative floor plan attached. Thanks!

What do you think of the bathroom and RMH in the center.

It has an inside diameter of 33ft/10m. Which is the maximum size of a round earthbag structure before needing buttressing. This design features two large bedrooms with spacious closets, efficient kitchen and loft for home office or 3rd bedroom. The inner circular wall could be built with recycled brick for strength and rustic effect. 855 sq. ft. interior plus 91 sq. ft. loft; 2 bedroom, 1 bath with laundry, and a little office nook with desk+computer; footprint: 36' diameter.
source

Don't forget about the outside space.
Grill, Outside sink, Outside Fridge, Rocket Oven, Rocket Stove, Solar Dehydrator, Solar Cooker, Turkey Fryer, Butcher Station,
Dining Table
Firepit and Sofa, Outside TV
Hammock and natural pool

Hi Lina,    Another build for inspiration:

Building-Rocket-Mass-Heater-Tommy

Interesting design! Is it something you are building?
Thanks for the teahouse link! That looks a bit smaller though. I guess the real question is how many square feet can an rmh heat in usda zone 5 when it is against the wall rather than in the center?

How about this:
1) Place the RMH in the open space along the bedroom wall.
2) And then run the chimney pipe thru the closet, to the exterior wall
3) Then punch a hole thru the exterior wall vs the thru the roof.

If possible, install pex piping into the floor, and the two week per winter when they forecast a deep cold, you can run it off/hook it up to your domestic hot water tank (solar/gas/wood/etc), and heat up the entire house.

1600ft of Pex piping + manifold + recirculating pump + is $750. $1000 if you get a separate instant hot water heater. For that small cost, I recommend installing it so that you have it incase you change your mind 10month or 10 years later to radiant in floor heating.

Thanks, that is an interesting thought! I think they are planning a crawlspace rather than a cement slab though, to limit concrete use to the foundation. Will have to look up radiant heat and wood flooring, I know that is trickier.
From your suggestions, I am inferring that you think the rmh near an outer wall would lose too much heat to that wall? Are there other ways to mitigate, in case they want the rmh bench to stay near the window? I was thinking they could build an extra, insulated wall behind it to reduce loss…

You will have to add a ventilation system to pull warm air into those bedroom from the open space. I can easily see you cooking in the summer with the open space/kitchen being 96F and the bedrooms being 80F or less. Likewise in the winter, the bedroom will be at 59F, while the air in the open space/kitchen, will be 75F and with the radiant (line of sight) heat making it feel like 81F. That will be a huge temperature difference, dry 81F vs damp 59F. You may have even noticed something similar in the pantry of forced air houses, with no vents in the pantry, esp if they have no ceiling fan.

The above is even before I touch on the topic of heat loss through the external wall. What is the proposed R-value of the floor, walls and roof?

All that said I do like the RMH bench/sofa by the window too, maybe you could have two RMH bench and alternate between which one you fire up?