Medium vs Fine grade Vermiculite?

[kebwi]

Re: Medium vs Fine grade Vermiculite?

The larger particles will insulate better. You don't really want dense cement in there, it's just glue to hold the vermiculite in a solid, so the bigger the vermiculite chunks are, the tougher time heat will have diffusing through the insulation.

[aeu99217]

Re: Medium vs Fine grade Vermiculite?

Nice one, cheers Les.

Also, your oven looks a peach!

Cheers Ross

[Les]

Re: Medium vs Fine grade Vermiculite?

I would go with the medium. During my build, I needed one more bag and it ended up being the fine stuff; think sawdust. (was in the same package, just a different store). I think when it is mixed with the Portland, it will not have as good as insulation as the coarser product.

Les...

[aeu99217]

Hi,

I've been reading up on the insulation hearth and as far as i can tell no-one has asked this question, but apoligies if has laready been crossed.

For making the insulation hearth, which grade of vermiculite is best, fine or medium?

Here's the link to the shop im going to buy them from ScotPlantsDirect|Perlite and Vermiculite| Orders ?49.99 and Over Free Delivery - Growing Needs - Perlite / Vermiculite

Many thanks for any help

Cheers Ross