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-   -   Vermiculite (Grade #3 or #4) (http://www.fornobravo.com/forum/f44/vermiculite-grade-3-4-a-20346.html)

Saovicente 01-27-2014 12:59 PM

Vermiculite (Grade #3 or #4)
 
Ladies and Gentlemen,

I have been pouring over threads searching for for a concrete (:D) number on which grade of Vermiculite to use for top and bottom of a build. ( I "of course" may have missed it or not poured thru enough posts)

As I have read and been told, the higher the number, the coarser the material and that it is better for insulating purposes for the vermiculite to be loosely poured over the ceramic blanket/dome.
Questions:
1) Which grade would be more efficient to mix with Portland for on top of the slab?

2) Which grade would be more effective for the top of the ceramic blankets/dome.


Thank You,

Sandro

david s 01-27-2014 01:26 PM

Re: Vermiculite (Grade #3 or #4)
 
I've tried coarse, medium and fine vermiculite and all work ok for a 5:1, but for a leaner mix like 10:1 I've found the finer stuff works better. Some have argued that the coarser stuff would theoretically insulate better. I'm undecided about this and any difference would be marginal anyway. The amount of cement mixed with the stuff is a far greater factor affecting insulation value. I've found the best mix for a lean brew to be a 50/50 mix of medium perlite and medium vermiculite and I also now throw in a handful of powdered clay with every litre of cement to improve workability. The correct amount of water in the mix is critical. I use 3 litres of water for every 10 litres of vermiculite, but if you use the fine grade it requires more water which of course has to be removed after.

stonecutter 01-27-2014 02:26 PM

Re: Vermiculite (Grade #3 or #4)
 
The ideally, aggregate on any mix design is graded, with fine-course particles.

david s 01-27-2014 02:35 PM

Re: Vermiculite (Grade #3 or #4)
 
Quote:

Originally Posted by stonecutter (Post 168762)
The ideally, aggregate on any mix design is graded, with fine-course particles.

Yes, this is probably why my vermiculite/perlite mix works well because the larger grains of perlite are balanced with some variable grain sizes of the vermiculite.

Saovicente 01-27-2014 07:50 PM

Re: Vermiculite (Grade #3 or #4)
 
2 Attachment(s)
Gentlemen,

I appreciate the knowledgeable know-how: I am getting closer to bringing all the pieces together to break ground on this outdoor creation.

Onward's to perfecting an insulated "cost-saving" creation

The intellects:
David:
I've found the best mix for a lean brew to be a 50/50 mix of medium perlite and medium vermiculite.


Stonecutter:
The ideally, aggregate on any mix design is graded, with fine-course particles.

Based on what I have read: It is to my advantage to create a 50/50 (Perlite( fine, medium or course) / Vermiculite (Fine, medium or course) mix.

I am still trying to understand the numbering of which is which (I assuming medium #3, course #4) hmmm, I need to find out where is 1 and 2 in all of this :confused:

I will call the manufacture tomorrow and get a better understanding of the numbering system.

I have not asked around for info on perlite, but the distributor I am dealing with gets the vermiculite from the same manufacture whom also makes perlite. Will get pricing tomorrow.

As always, I sincerely thank you for your thoughts, which are much appreciated.

Sandro

PS: I have attached two *.pdf for review for other newbies who comes upon this thread. The data may be of interest. The information is from a company which manufactures both products in MA (US).

stonecutter 01-27-2014 08:13 PM

Re: Vermiculite (Grade #3 or #4)
 
For what it's worth ( probably not much) I have used both, I prefer Perlite.

david s 01-28-2014 03:33 AM

Re: Vermiculite (Grade #3 or #4)
 
Quote:

Originally Posted by stonecutter (Post 168786)
For what it's worth ( probably not much) I have used both, I prefer Perlite.

Except that it contains some fine powder, presumably fine perlite particles that are irritating if you breathe them. Vermiculite doesn't seem to have these small airborne particles.

stonecutter 01-28-2014 04:31 AM

Re: Vermiculite (Grade #3 or #4)
 
Quote:

Originally Posted by david s (Post 168789)
Except that it contains some fine powder, presumably fine perlite particles that are irritating if you breathe them. Vermiculite doesn't seem to have these small airborne particles.

Everything has dust that can be irritating, including vermiculite...and if you are using fine grade, you'll get plenty of it.

david s 01-29-2014 03:00 AM

Re: Vermiculite (Grade #3 or #4)
 
Quote:

Originally Posted by stonecutter (Post 168793)
Everything has dust that can be irritating, including vermiculite...and if you are using fine grade, you'll get plenty of it.

That may be true, and the manufacture of these products will vary from place to place, but the perlite tha's available to me has the irritating dust while the vermiculite doesn't have any. Can't speak for your supplier.

stonecutter 01-29-2014 05:31 AM

Re: Vermiculite (Grade #3 or #4)
 
I can get both kinds. Block fill perlite is fine and dusty, horticultural grade has almost no dust at all... Which is what I used.


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