Building a RMH/Rocket stove

Hey all. My wife and I bought a knew home and my family has heated with wood since well before I was born. I'm looking to put and RMH or rocket stove in our basement to heat the basement which would in turn heat the upstairs floor which over time would rise to gradually heat the upstairs. Now I've seen and watch probably 2 dozen videos and read forums, but I can't find a good drawing with dimensions for a few things.
Now I've seen several of the designs out there. We are looking to do a little edgy/up to date design. So a few outlying questions;

Best size for exhaust pipe 6" 7" 8"??
Has any one done an open chamber around their exhaust instead of solid? If so what kind of heat difference is it and do you lose more BTUs etc..
Anyone have any other designs besides 55gal drums or repurposed material. I have a buddy who's company does rolled steel etc..

I'm putting this in a brand new house in Michigan. My wife of course doesn't want anything that is ugly for simple terms.

So any help would be greatly appreciated.

nick marcinkowski wrote:I'm looking to put and RMH or rocket stove in our basement to heat the basement which would in turn heat the upstairs floor which over time would rise to gradually heat the upstairs.

Forget about this, it's know not to work. Whole house stack effect fighting with the draw. Feeding intervals and fuel adjustements being impossible to follow. Main source of heat being radiant, not convection, it doesn't rise either. Etc.

If you have a fireplace in your living space, then, may be there's a better way.

A basement RMH *might* work in certain conditions. If the house is one story and relatively tight so there are not a lot of air leaks near the roof, and if you plan to use the basement regularly as a living space, it is possible that you could have a successful build. I wouldn't guarantee it, though. Far better if there is a central space on the main floor which is well supported, or can be braced in the basement without causing interference with anything important.

As for appearance, there is no limit to how you can make the "barrel" look. For best function, it should be one layer of metal, but the shape and material is up to you.

I don't understand the question about "an open chamber around their exhaust instead of solid." What element are you talking about here?

Glenn... most of the designs I have been looking at have been solid mass chambers. As in the exhaust system is either covered in some sort of insulation (fireclay..vermitculite etc..) I was wondering if anyone has ever seen or works if you do an "open chamber" as in box around the exhaust pipe (lets say a 4 foot chamber around it and create vents on the chamber for the heat to escape (possible even put a vent van inside to pump the heat. I did find for a design the one that zaugstoves.com made which was more modern.

Glenn Herbert wrote:As for appearance, there is no limit to how you can make the "barrel" look. For best function, it should be one layer of metal, but the shape and material is up to you.

Well, with batches, the metal isn't that much needed anymore. And to me, batch boxes are soo much more convenient. My latest oppinion on the stuff, make the "barrel" on the heat riser, a brick bell, with the heat riser to the side; this brick bell being big enough to house a oven next to the heat riser. And use a metal oven door, for "direct heat" release. Then channel the heat under a cooktop, next to the bell/oven combination. For simmering dishes. The deep frying being taken care of by the hotplate/cooktop above the fire directly, as a ceiling of the firebox.

nick marcinkowski wrote:Glenn... most of the designs I have been looking at have been solid mass chambers. As in the exhaust system is either covered in some sort of insulation (fireclay..vermitculite etc..) I was wondering if anyone has ever seen or works if you do an "open chamber" as in box around the exhaust pipe (lets say a 4 foot chamber around it and create vents on the chamber for the heat to escape (possible even put a vent van inside to pump the heat. I did find for a design the one that zaugstoves.com made which was more modern.

Zaug stoves are just a product, not a rocket in my opinion.

Things which are not along the lines of a rocket. Uninsulated feed tube, and slanted. This is known to lead to bad combustion, and the slanted feed leads to bad mixing.

Secondary air under the heat riser's base? Well, this is cooling the hotert part of the stove, where it should be inferno X10!

No burn tunnel, which is the carburetor of the rocket stoves, with the feed tube and heat riser's elbows ensuring the best mixing possible.

So, to me this is not a rocket.

I don't even find those prety.

And the "direct plenum" where the pipe is exhausting the barrel at 90°, and potruding inside is also known to be a restriction in draft. The ring projection there should be at least 3 times the cross sectional area (CSA) of the heat riser at this point with this type of arrangement.

The best thing you could do, at this point, since the winted is on it's way out. Start experimenting with proven designs in your backyard, stuff cobbled up with bits and bobs. And see what you think and feel. Then, when you have found that it might suit you. See if it's adaptable into your home.

Check my post here for examples of Batch boxes, which i'm partial to

https://permies.com/forums/posts/list/52643#427013

You can see a J tube with brick bell bellow too.

Once you know how to build the "core" of a rocket. You can addapt it prety much to anything. Modern or old looking. Pebbles, earth plaster, tiles, stainless, mirror or glass surfaces. Keep the barrel, and make a brick lattice around. Or a engraved copper shield, which serves as a convection sleeve. Prety much everything is possible. Even the use of stone walls as mass. If you don't want to have a bench or a bell.

most of the people i have seen that have built multiple rocket stoves usually go bigger instead of smaller. the batch is the most convenient.

It seems like an open chamber around the exhaust duct would just be a way to corral the instant radiation, not really store it. It would be less effective at getting the heat to the space. I suppose if you want to blow the heat somewhere else, it would work for that.

The exhaust duct is never covered in insulation; it is always heat-conductive massive material of some sort. That is probably what you meant to say. Fireclay qualifies, though it is overkill (a more specialized product than there is any reason to use), but vermiculite has no place there except to shield a combustible wall from the mass.