Insulation question...

[Stone Mason1]

I am making a refractory dome and am after insulation advice.
Perlite is sooooo expensive here $30 for 5 ltr bag : (
I will need around 100ltrs for the size of my oven.

I have been looking at adobe pizza ovens, they use clay slip and sawdust mix.

Do you guys think it will be fine to use over the Ceramic Fibre, then allowed to completely dry then veneer with stone?

Apparently the sawdust burns and leaves voids in the clay for air gaps for insulation.

Cheers in advance.

[dmun]

Re: Insulation question...

If you are using the ceramic blanket, you don't need vermiculite concrete. It's just a cheap way to achieve the dome shape before stuccoing. You can build an armature of wired-together expanded metal lath in the shape you want, and apply your stucco over that.

I wouldn't put anything there that's going to burn.