is this fibre board ok??

[umabatata]

Thermal insulation shop sent us this as a cheap offcut (900x1200mm) saying it'd be ideal for pizza oven base insulation. I'm concerned the compression is too much for the weight of the edge of the dome rather than the weight of the floor, and that this will cause inside edges of floor bricks to be pushed up. An asbestos layer would do the trick, but is a bit deadly (and hard to come by, and I'm not going to cut it)
Thoughts?

one solution would be to cut the floor bricks so the 1st layer of the dome site outside them rather than on them, then the squashing of the outside won't effect the cooking floor as much.

[RandyJ]

Re: is this fibre board ok??

That is definitely not what you want. You would be better off doing the vermicreete with vermiculite and portland cement. That is way to squishy and will lose all insulation value. All the ceramic board I have seen looks like the picture I will attach. If you try hard you can squish it a little but is very stiff and rigid. You should try to find that or do the vermicreete.

Randy

[umabatata]

Re: is this fibre board ok??

Thanks for your reply.
I guess I kinda knew that was the answer but it's always good to get someone to confirm. I have now ordered some calcium silicate board (that was also damaged and therefore supplied at cost) from a different company. Still a lot of cash on this oven though. It is all the talk on these forums that is keeping me buying good stuff for the insulation. Keen to have a oven that is useful for more than a few hours like some friends ones.

[RandyJ]

Re: is this fibre board ok??

I did very good on my expenses through the stand and dome build. Including insulation, but I am now almost 50%over on the whole building due to how I decided to finish off the oven. The right insulation is just a small amount of the whole cost. So best to do it right. You will spend most of the money anyway. Good luck.

Randy

[DavidApp]

Re: is this fibre board ok??

Hello umabatata

Here are photos of Ceramic Fiber Board and Blanket. The board is a much more dense product and will not compress. At least it only compresses a small amount unlike the blanket.

David

[umabatata]

Re: is this fibre board ok??

Thanks David
I also have a roll of ceramic fiber blanket and this product is much more rigid than the fiber blanket, yet not as firm as a board. Very odd stuff. I think it is wall lining or somthing. I am not sure I can use if for the dome as it is not flexible. It feels like it would break rather than bend around a curve. If I can find out what it is I might try and sell it on. I considered putting it under the new boards I have ordered, but then it might still mess things up as it is not rigid... not sure