Foamglass or CalSil

[JohnR]

I can get 3" Foamglass or 2" CalSil insulation block for about the same price. Any recommendations as to which way I should go. My hearth is 7" thick concrete and then I'll be putting one of these insulating boards underneath the floor... Which would you choose?

Thanks!

[boerwarrior]

Re: Foamglass or CalSil

CalSil!

(and adding this sentence so that my message is more than 10 characters long!)

[vtsteve]

Re: Foamglass or CalSil

Both! CalSil on top (that's what I did).

[Yeager]

I like the "Both" idea, but can't seem to find anyplace that sells Foamglass in the Minneapolis area - any ideas on how/where to find it?

[UtahBeehiver]

EJ Bartells sells it and can be shipped, check with your local refractory building material suppliers.

[vtsteve]

Possibly at Tri-Star Insulation: