Rigid Perlite insulation

[spacevan]

Has anyone hear of or tried to use perlite pipe insulation for the heat riser? It can be heated up to 2000 degrees F. Liquid sodium silicate is used as a hight temperature binder.

These web sights have some more info about it. www.schundler.com/composites.htm
www.silbrico.com/hightmp.htm

[canyon]

Thanks for the links! That stuff looks great! I bet it aint cheap though. It would be interesting to see what it costs for what size pipe lagging.

[spacevan]

I talked to a manufacture of rigid perlite insulation and there product will not stand up to direct flame.