@Jenw I have been looking in to Frost Protected Shallow Foundation. Google that term.
They do this much further north than Missouri or Kentucky. I will let your search explain it, but very worth looking in to. Keep in touch, you are close! JW

Sums it up nicely!
This is my understanding as well.
That is why I was confused with the YouTube guy,, Honey Do Carpenter,
when he insulated his exhaust stack just before exiting the home so that it would draw better.
From what I have seen,, designs loop the exhaust then bring it back up to
rise by the original riser so that it gives it a bit of a heat boost to draw on out further.

That's what i'm talkin bout! Bring it on home brotha!

I have a lot more to learn about Rocket Mass Heaters but what thru me off this guy,,,
Honey Do Carpenter youtube that you are referring too,
is that he throws a lot of heat out the stack pipe rather than keeping it in the home
stored in "Mass".
I might not be understanding him correctly, but I have tried to study what he is doing.
He fixed a stove, tore it apart and his fix was to insulate the stack pipe so that the pipe stayed
hot and drew out the heat better.
I will stay tuned, appreciate the conversation.

Great info and blog. Looking forward to following along!

Please keep us posted, sounds like you are on the brink of success!

@zander Sounds like you just made a crock pot! Any photos yet?!

A topic after my own heart!
I am not an engineer and have NO experience with Aircrete, Domes or Ferrocement
In my head (which can be a dangerous place to visit)
over the last month (which is when I discovered Aircrete)
I have been thinking they would all work synergistically well to go underground!
Build your Aircrete Dome then put a strong coat of Ferrocement over it.
"Strong" is the operative term here to define.
I am thinking that there are Ferrocement Underground Structures and some even in the shape of a dome.
Aircrete would I guess just offer the insulative properties and ease of building the dome.

For extra strength maybe build a dome first out of electrical conduit (or other struts of choice). Fashion a mold to build triangle blocks of Aircrete mortared together with Ferrocement supported first by the dome grid, then covered with a Ferrocement strong coating fabric, maybe even thicker than normal (whatever those Ferrocement Underground Dome builders have already calculated). You could also have the gaps in the blocks large enough to tie all the gaps together with rebar.

Ok, thanks for letting this neophyte get all this off his chest!
Comments are anxiously anticipated!

@zander said in Aircrete and earth-berming:

Impervizante roof paint

I am googling and trying to find info on this product to no avail.
Do you have another term or brand name?
Thanks, this gringo is too far north to be familiar with such a product!

How does Aircrete lend itself to the idea of Rocket Mass Heater construction?
As you know the idea of the "Mass" component in such a heater is to absorb heat from a "Rocket" type stove, acting as a battery to release it after the fuel is all consumed in the stove.
Typically people are using "Cob" and I have seen others use a box filled with pebbles with a rock or granite top. I would post links and/or pics but I believe this crowd would be familiar with this concept, if not google offers extensive discovery.