Vermiculite or Perlite, what's the difference? Tools, Tips and Techniques Discuss Vermiculite or Perlite, what's the difference? in the Pizza Oven Design and Installation forums; I placed my order for the supplies to start my project and the masonry supplier only carries Perlite. Is that ...

[DimTex]

I placed my order for the supplies to start my project and the masonry supplier only carries Perlite. Is that the same as vermiculite? I asked if it was silicone coated and he said no, but I am not sure if the guy would have known in the first place.

[Neil2]

Perlite will do the same job as vermiculite. Perlite is a "blown" rock.

Make sure it is the coarse grained perlite. Particles should be in the order of 1/8 to 1/4 inch or so.

I used half vermiculite / half perlite in my insulating layer.

[dmun]

Perlite works fine. It's what I used, and I didn't have any grains as big as quarter inch. It has the advantage, being white, of having a visual indication of when it's fully mixed with the portland.

[timo]

I just finished working with perlite and can report that it's easy to work with and mixed well with the portland. I dry mixed the portland and perlite then added water and it mixed well. With a 5:1 perlite to portland ratio I used 8 cubic feet of perlite to about a bag of portland. Hope this helps

[DimTex]

Thanks for the information

David