John Trinos

Rufus Laggren wrote:> [wall vs. roof penetrations]

Short term, wall is easier. It's lower, easier to reach and usually easier to cut and patch and make weather proof. Long term it's a wash and roof penetrations may look better (or not) and make for better layout for your flu runs (or not). Roof definitely needs to be closed and weather proofed correctly and carefully and this detailing is not as easy for most people as working on walls.

Rufus

What makes having the wall connection a wash compared to the roof? On another note, the roof is metal, would this complicate things compared to traditional?

Sean Rauch wrote:If it was me I think I would start out by shoring up the floor turn I'd spray foam the whole underside on your floor, bat insulation really isn't a good product in a crawlspace floor anywhere and you don't really the inside of your house exposed to the unsealed ground (loose poly like you have there really isn't a barrier). You can find your home pulling gasses like radon out of the soil into your home if you don't properly seal the underside.

Then I would move the electrical in the way of your RMH, so you can get it close to the wall and save a bunch of space.

I know it sounds like a lot of work for a RMH but the reality is you'll be much happier and better off for it.

How much of a budget would spray foam insulation run for nowadays? I'd imagine I'm better off hiring someone to do that.

Thanks for the input, guys! While not in a rush to jump headfirst into this project, I'm doing due diligence first, because the main factors that concern me are fact that the house IS on a mortgage (which I plan to pay off asap) which complicates things since home insurance bureaucracy is in the equation, etc. It's definitely a home I really want to spend a long time in. If that major hurdle somehow can be overcome, I'll be more than willing to proceed.

After looking at the suggestions, the bell design would probably more suitable for the space than the cobb bench. Regardless of which design, I'll need definitely to install crawlspace jacks to support the weight.

As for location, I should've clarified more - the wall between living room and room 1 has a front door next to it, and the wall between bathroom 1 and the kitchen has the backdoor and a mini washer/dryer room next to/in it as well. Otherwise I would've picked those places as the more logical choice Are there any pros/cons to running the exhaust pipe through the ceiling/roof compared to the side wall?

Oh and I do have the Rocket Mass Heaters book. Great material, still in the middle of reading it at the moment.

I'll see what I can figure out. If anyone out there has had to overcome the home insurance hurdle, please share.

-John

Hello! I'm new to the forum and recently learned of the rocket mass heater concept.
I recently moved out to the woods, and was originally considering a conventional wood burning stove.
I figured a RMH instead would be far more handy than relying on the standard AC / heating unit.

Here's the layout of a 7.5 ft x 2.5 ft area I want it to take up. It's spaced a bit from the wall so that the vent and electric outlets are still accessible [see Layout pic].

One downside is that it's located one one side of a ~1250 sq ft house [see House Layout pic].

If room permitting, it'll have a bench for at least one or two butts to sit on.
What concerns me is the total weight the firebricks and cob would have. I went in the crawlspace and took a look at what exactly would be supporting the dead load: [see Crawlspace view pic]

Some nagging questions I have are:
-Before I can even think of building the thing, are crawlspace supports needed for this? How heavy will an RMH of that size be?
-Considering the size and location of the RMH, how much of the house can a RMH of this size realistically heat?

I'm definitely going to attempt to build a prototype outside the house somewhere as a proof of concept for sure, but ultimately, an indoor unit is highly desired.

Thanks in advance!
John