lorne babb

Hello Permie Pyromaniacs!

After some measured success in building a RMH (much thanks to this forum) , I am taking on an old boxy fireplace. It never drew very well, despite having a good flue and smoke chamber, so I am thinking converting it to the Rumford dimensions (following the specs from Rumford.com). But, in typical fasion, I have no idea what I am doing! I know that Erica and Ernie mentioned that it can be done. But, I don't want to do a huge messy rebuid. My idea is to mortar up fire brick using fireclay/sharp sand and hand plastering a "throat" using metal lath and natural plaster.

But has anyone done it?

Any ideas what I should use for plaster for the "throat shape"?

Thanks for any help.

Lorne

Good point, foil on the floor would not be clean long in my shop, thanks.

Glenn,
Thanks for that feedback, I was quite worried about the spacing of the bricks, as I came by the 12" spacing without much evidence. Hey, bricks are cheap ($.35 each). So, I'll go every 6 inches with the bricks supports then.

"the book" says to glue 2 layers of aluminum foil on the wood floor. Doesn't that reflect radiant heat away from the wood? But I guess foil above and under the bricks couldn't hurt.

Thanks again.

LB

Satamax,

Thanks for that, but to be clear the sheet material I am using is a cement board (Durock) sold over here in N.America. So, you think a total of three layers or about 1.5 inches?
Cool, thanks I was wondering how many pounds per square inch it could take. I guess I should put a thin layer of thin set mortar between each layer.
I have some nice old brick, likely 2 courses would give a good base volume for the perlite.

thanks

LB

I am attempting to build an RMH from the 6" Daybed plan from Ernie and Erica's plans. I am unsure how to build the platform above the floor and how to contain the perlite insulation layer. I have beefed up the joists under the footprint of the stove, so that part seems good.

What the pics below show is 1/2" durock on concrete brick on edge spaced every 12 ". The total footprint of the stove in roughly 3x10 feet.
My questions are 1. does my construction look ok so far, and 2. How to hold the perlite on the durock sheet, and how deep for that matter.
By the way, great forum, I've learned a ton.