Which brick to use??

[ClayWood]

Hi all,

I have recently bought some 2nd hand bricks out of a pottery kiln. Half are low density and could be cut with a hacksaw, which I now know are just for insulating and no good for the oven.

The rest however are heavier and higher density, they are meant to be good for the oven but im not convinced. They arent as heavy as a red clay brick but are still alot heavier than the low density ones. Any input would be great!

Ill add pics of the higher density, most are the type with the "Childs" print on them.

Cheers

[UtahBeehiver]

The insulating bricks (IFB) could be used as insulation under a fire brick floor. IFB has a typical K value of 0.09 BTU *in/(hr*ft2*F). There have been many Aussie builds done with IFBs under the floor, Actually IFBs are quite expensive, 3-4 time more that standard fire brick in cost. The two examples of the regular bricks appear to be standard refractory bricks and appear to be pressed vs wire cut which typically are better.