we have built the base.....

[Dino_Pizza]

Can you guys tell me if that insulating concrete can be left out all together and just use the 3" or 4" structural concrete and then use FB Board (or any hi-tech insulating rigid board) under the oven? I plan on buying and installing an FB Primio later this summer to put on this.
Thanks, Dino

[gjbingham]

Yes Dino,
That is the upscale method. Perfect way to go.

[Acoma]

And don't place the insulation board on all areas of the hearth, just enough to cover the entire base unit (entry and dome). The rest of the area can be concrete to balance the height, allow for tiling, etc....

[JUBILEE]

thankyou for that. i'll check out some others in the gallery before we get started. everyone has such great ideas! the plan is to begin tomorrow if the rain stays away so i'll let you know how we go. we are worried that we have gone too high with the base? what would be the thinnest depth of the insulating layer that we could get away with? we will be using fire bricks for the cooking floor.

[Acoma]

2" of insulation board is minimum. 2" of board equals 4" vermic.

[DrakeRemoray]

Originally Posted by JUBILEE

we are worried that we have gone too high with the base?

Actually though, sometimes higher is better. It is more comfortable to work the oven if you don't have to bend down to look in it at all. Look at professional pizza ovens, they are often up a shoulder level...

[Neil2]

I used a mix of 1 part cement, 6 parts perlie and 6 parts vermiculite. I think the mix makes for better worability.

Be sure to mix it dry first then slowly add water then mix gently. It does not take much water. Avoid overmixing when wet or you will break down the perlite and vermiculite particles - reducing the insulation effect. Don't use a machine - do it by hand in a wheelbarrow.