Perlite

[mattmania]

Does anyone have experience with Perlite/Concrete mix? I actually want to make a new hearth base out of it...originally I was just gonna frame out 2 inches of concrete. But then I thought to add some fire clay. Cant find the fire clay locally, so I am gonna use Perlite. The only question is the ratio. I saw some ratios calling for 2 parts perlite to 1 cement, or even more than that. But I doubt that kind of mix could be hard enough to hold a 400 wood stove, could it? The other option is just to make a concrete hearth base, and just add 10 percent or so perlite by volume.

Any thoughts?

 

[bholler]

what stove is this for what r value are you trying to reach?

 

[TheRambler]

Why add perlite at all?

 

[mattmania]

It is for an Englander, which supposedly requires R2. So using the Perilite, I am thinking I can get that in about an 1.5inch or so

 

[begreen]

Not sure if you are going to achieve that goal of R=2.0 with just perlite mixed. This publication may help you out.
(broken link removed to http://www.hessperlite.com/siteGFX/perlitePDFs/Perlite-Concrete-Overview.pdf)