As far as fire resistance goes, it is terrific. I have put my propane torch with the 1" tip on a slab about 1" thick for at least a minute or two until it was glowing red. My hand on the backside never felt any heat at all. (Actually I watched the rep demonstrate this for me first before I tried it.) So in that regard, my opinion is it makes a better fireblock than even hollow concrete tile, which transfers the heat around more than this stuff will.
