Masonry Heater for my Yurt

[Bob Rowlands]

Full size masonry fireplaces sit on a pad or other structure that bears on the ground. This is way lighter than that, but a ton is way the heck too much weight for a floor frame. Thanks for the photos hierony.

[hierony]

Well, I might say a properly designed/very stoutly built wood frame _could_ hold up a ton spread over a good 5 sq feet (400 psf)--wood is pretty decent in compression. But I don't think it would be worth the effort/cost & it's good to have a non-combustible support under a wood stove...

[hierony]

Got the facing done--it'll eventually get covered with plaster.



Now to cap the core:


If I can find reasonably priced chimney pipe around, I might be able to get it burning soon!

[Bob Rowlands]

Nicely done. Thanks again for this thread.

[hierony]

The heater is basically done now. Air inlet & cleanout ports are mortared in, firebox door is in place (screws in frame hold holes drilled in brick facing) & insulated, all doors/ports sealed on the outside with silicone to prevent air/smoke leakage.


Core is capped with ~3 inches of perlcrete & 1/2 to 1 inch of thinset mortar.


Now to get the chimney figured out. I was thinking of using leftover ceramic

insulation

to make my own double-wall chimney pipe, but the minimal stovepipe/chimney (~8 ft) might not give enough draft & I wouldn't easily make more. Plus good quality stainless steel pipe in the right sizes wouldn't really be cheaper. So I bought some chimney pipe...

Bob, you've mentioned trying to make your own insulated double-wall pipe with fiberglass

insulation

, right? I think you said it didn't work well but didn't say why?

[Bob Rowlands]

It burned. Not burned really, it kinda cooked. Really really weird when I pulled it out. Don't insulate between pipes with fiberglass.

That is one fine looking piece of work. VERY nicely done.

[Bob Rowlands]

Can't say enough positives about that stove. I'm really floored by the build. Thanks again for putting this on here for all to see what a 'I'm GONNA do that.' attitude will get you. No fear. Go for it.

[hierony]

I wondered about that--it's always good to check material properties. It looks like fiberglass insulation burns/melts about 1000 F (EngineeringToolbox, usually good general info), so it should technically have been alright. I thought I saw something about it really only being good to 600 F (melting temp?) or such though. The ceramic stuff I got for building the stove is rated to 2012F, so definitely good--but too much work for minimal savings :P

I got the chimney up, though I need to get the roof flap sealed up properly again. I'm learning to build fires in the dang thing, plus it's only supposed to get 1/3-1/2 firebox capacity the first week so it dries out slowly/doesn't break mortar joints. I'll post chimney pictures once I get it all sorted.

[Bob Rowlands]

'Dang thing?' Are you having second thoughts?

[hierony]

It's the moment where all my ideas finally meet up with the hands-on part--a little frustration, some learning & adapting, then things should work. I seem to forget how to light fires effectively. In messing with the crown ring flap the yurt is a little more drafty until I fix it, and our area just dropped to the 30's with some snow...

So far I've resorted to a propane torch, dousing the wood with ethanol, burning a few free newspapers. Now I'm on to actually making kindling, plus I found the real matches. The heater isn't supposed to get full firings yet & it's slow to fully heat up, so I won't know how well it actually works another day or so (after I get my fire-making back up to par).

I'm regretting not getting it finished before the weather got cold :P