Hearth insulation

[huff]

Thanks to many of you who have posted on Hearth insulation. I have a Mugnaini Medio 110 oven kit and the Mfg. calls for 6" of sand under a 3" concrete base under the hearth. They say that while the sand acts less as an insulator but more as a heat sink to develop thermal mass and keep the floor hotter longer. Although it does take 20 minutes longer to come to temperature. Any thoughts on this design vs perlite/vermiculite concrete mix?

[Laurentius]

Re: Hearth insulation

It sounds like something counter productive to your needs! You need the thermal mass under your hearth not to be a drain for your heat, the insulation is to keep it (heat) from being sucked out. Unless, I've gotten it wrong?

[brickie in oz]

Re: Hearth insulation

Any thoughts on this design vs perlite/vermiculite concrete mix?

Do you have a forest of wood to burn?
Do you have countless hours to waste stuffing the forest into the oven?