Building a RMH into a new foundation.

This spring I'll be pouring an insulated slab foundation for a  14 by 64 mobile home I've purchased.
I want build into that a 6 ft wide Mass that will eventually go to a RMH that I will build into an attached mudroom.  Question is what should I be telling the concrete company to get this done? Should I have them attach an insulated trough that I'll fill in with something else? Or maybe just some rebar that I'll use as attachment points and build on top of it.
While I'm at it should I do anything to the trailer while I'm not living in it?
I appreciate any spoon feeding on the subject thank you.

Mike,

8" thick slab for the heater. Reinforced with 0.5" rebar grid 8" OC on the top and the bottom of the slab.
It will last. I would not make it thinner, even if it seems strong enough, or with less rebar, even if it seems strong enough. I saw bad foundations too many times, too thin and without proper reinforcement.

Would a rocket stove work with a 40-60 ft mass? Most pipes don't seem to go more than 20 ft.
I'll be making the slab this week. I've decided to double the width the slab. I'll be putting a concrete wall against the trailer and building the mass at the base of that. With a single pipe going to to a vertical chimney. if budget allows I might be building a 20 foot greenhouse/sunroom on one end. so a diverter to have an optionally heated mass in that room as well.

Wow, big decision to make in a short time.

I can't speak to the engineering of the rocket stove / RMH. It seems like a finely tuned beast.

That said, there are many ways to draw or push hot smoke through a thermal mass. This has been done throughout history.

Mike,

Piped mass "went out of fashion" . It's better to build a low bell bench - easier to clean and gases will do the job in a less restricted and natural free movement way. If you share your planned layout on the home plan, we will help.

To be honest, I'm winging it. I'm going to design the addition around the mass. But that won't be for a week or two when I get a breather from getting this mobile home moved.
But I have the heavy equipment this week so it is what it is.

The mass was going to be a brick frame 5 ft high with perlite layered on the bottom and a straight pipe going at an angle from one end to the other.  Filled in with Cobb. Then capped with something.  The floor of the addition might be 1-2ft off the  base of the slab.

Hey Mike. A rough sketch would help.

From what I imagine it sounds like very little heat exchange surface (inside of the pipe) to a lot of thermal mass. That would mean the mass never gets hot.

There’s definitely a maximum of pressure loss (that translates to a maximum length of pipe and number of turns). But it depends also on what rocket you want to build.

I'll have more time than I thought and discussing it with my builder. I'll be building two smaller 7inch systems instead of trying to make one huge one. I'll be able to find a plan to my liking that fits that. I'll update as I go.

Mike,

In what climate are you located?
Will the building be insulated, and how much, walls and roof ?
Will you have an open space or separate rooms?

I took a pause to attempt to finance the construction of a house. But those costs ballooned fast. So back to what I already have.
Its an old 16 by 70 mobile home on a 24 by 70 insulated slab.
I want to build it on the extra slab and build over that. The home is about 4" off the ground.
I want to have it radiate underneath as well the livable areas.

Mike,

A dedicated slab is a good choice as mobile home slabs will be usually minimally thin and insufficiently reinforced (if at all).
How do you want to radiate heat through 4" space?
Centrally located RMH should heat the key areas in a light mobile home. If you shared the plan we could help with heater placement.

Cristobal Cristo wrote:Mike,

A dedicated slab is a good choice as mobile home slabs will be usually minimally thin and insufficiently reinforced (if at all).
How do you want to radiate heat through 4" space?
Centrally located RMH should heat the key areas in a light mobile home. If you shared the plan we could help with heater placement.

Its an 8" slab with  a grid of the rebar and a deeper trench around the parameter and at the 12" mark which is where the trailer starts on the slab. I was thinking of placing left center so the bedrooms can open there windows into the area which it is in. With the barrel and vertical chimney right outside the entrance.

In this case it may be sufficient. Is it a grid on both sides of the slab - upper and lower, what spacing? Dedicated slab will give you additional support that will distribute the weight or the slab.
If you have a choice II would suggest to have it close to the bathroom/living room area as sleeping in colder air is great, but bathing not so much - at least for me.

Cristobal Cristo wrote:In this case it may be sufficient. Is it a grid on both sides of the slab - upper and lower, what spacing? Dedicated slab will give you additional support that will distribute the weight or the slab.
.

six inch grid in the center.
Is whe erny and erica book out of date? I was thinking of copying the 8" j tube bench.  

Ernie and Erica's book is still the best reference for J-tubes and what surrounds them, but the piped mass concept has been superseded by the bell concept.

You can make a bench-style bell in about the same footprint of a piped mass bench. We can give you specifics if you have your core design solidified, and construction materials basically figured out.