Can you build right on the vermiculite mix?

[jonesz]

I have built my base and hearth. The hearth is one half concrete (lower half) and the upper half is insulating concrete (vermiculite cement mix) My question is, do I build the oven right on top of the vermiculite mix with a layer of leveling clay? It doesn't seem to be real solid enough to tolerate the weight of the oven. I did this according to another site before I saw this one. The front part is full thickness concrete where the front of the oven would be, but the rest of the hearth is split 50/50. vermiculite on top of concrete where the actual oven would sit.

[Tonyp]

Re: Can you build right on the vermiculite mix?

How thick is the vermiculite/cement mixture and do you have an idea of the ratio you used in the mix?

[merrilljima]

Re: Can you build right on the vermiculite mix?

I plan a vermiculite 6:1:1 -- 3.75 in deep on a 3.75 in base slab



Jim 48 ID PC Florida

[jonesz]

Re: Can you build right on the vermiculite mix?

Both are 2.5 inches thick. Reinforced concrete and the vermiculite mix. The mix is 5-1 dry mixed and then a little water.

[Greenman]

Re: Can you build right on the vermiculite mix?

If you have 4" of reinforced concrete under the vermicrete then you should be fine.

[jonesz]

Re: Can you build right on the vermiculite mix?

Thanks Steve. I wrote 2.5" I meant 3.5" each. I split the depth of an 8" x 2" board on the sides of the form.

[Greenman]

Re: Can you build right on the vermiculite mix?

You should be good to go with that. Good luck with your build. It is a rewarding project.