Ceramic FB or Vermiculite Concrete

[Sketchy]

Hi everyone.

I am thinking of building my first oven. I have found a supplyer of fire bricks but i had a question of weather i am better to use Ceramic FB or Vermiculite Concrete. The supplyer said that Ceramic Fire Booard and blankets are carsnogenic and advised against using it. He did offer somthing called body soluble blanket that he said id the same thing but safer or Vermiculite Concrete.

What do you guys think what should i use. Are there dirrernt types of Ceramic FB.

Any advice is appreciated.

Thanks

[dmun]

Yes, there are different grades of fibers in refractory boards and blankets, and in my opinion you shouldn't be breathing any of that stuff, including the dust from vermiculite, concrete, or brick cutting. The danger is not that they are carcinogenic, although some of them are, but that any sort of crud can lodge in your lung tissues and cause silicosis down the road. Any sort of commercial building material is marginally safe, as long as you take the proper precautions, in this case using a proper respirator, not those throw away paper masks.

[david s]

Vermiculite seems to have less dust than perlite. That's why I prefer to use it. I also stay away from anything that is even marginally carcinogenic.

[david s]

There is a board called mill board BIO that uses safe ( ie water soluble fibres) otherwise the safest is to use vermiculite/cement, but remember that the more cement you use the less the mix will insulate. About 12:1 is about as weak as you can go and still have the stuff stick together. Any more than 5:1 and you won't have a mix that is going to insulate particularly well.

[Neil2]

Use a 5:1 or 6:1 mix for the load bearing area, i.e. under the hearth bricks. Use the 12:1 mix for the non-load bearing insulation over the dome.

Mix gently by hand. Vigorous mixing will break down the vermiculite or perlite particles resulting in a denser and less insulating verimicrete.