 Re: silly questions
Quarter inch should do fine. The real work of holding up your oven is done by the reinforced concrete support slab. Put an extra piece of rebar in the front part of the slab if you're worried.
There were some vermiculite deposits that were asbestos bearing, but they are not mined anymore. Any new vermiculite should be asbestos free, and say so on the bag.
I bought my perlite from an eBay vendor. The shipping was more than the material. |