#1  
Old 08-17-2009, 09:36 PM
Apprentice
 
Join Date: Jul 2009
Location: Cochrane, Alberta
Posts: 104
Default Insulated Hearth

I've found a product called Zonolite. It is vermiculite with an additive that reduces or prevents the vermiculite from absorbing moisture. It is manufactured and sold by GraceConstruction. It is a loose insulation that is used for insulating cement blocks by pouring it into the holes in the cement blocks.
Has anyone else heard of this product and can I use this material and mix it with cement to make the insulated hearth?

If nothing else, I will use it to fill in around the dome. I have been having a problem trying to find bulk vermiculite that is cheap.....

Last edited by Spunkoid; 08-17-2009 at 09:39 PM.
Reply With Quote
  #2  
Old 08-17-2009, 10:19 PM
Les's Avatar
Les Les is offline
Il Pizzaiolo
 
Join Date: Sep 2005
Location: Carson City, NV
Posts: 2,858
Default Re: Insulated Hearth

A VERY quick google tells me to RUN! This may be old data - a common issue w/ the web. The vermiculite we are buying today is free of the nasty stuff (Or so we are told).This could be a dump

WR Grace mined vermiculite in Libby Montana during the 1960's and 1970's and packaged it as insulation under the trade name Zonolite. Grace also had a number of processing plants around the United States where it turned the mined vermiculite into Zonolite. Zonolite was sold nationwide until about 1985. The Federal Government estimates that it may have been used as insulation in as many as 35 million homes. The Environmental Protection Agency warns that if Zonolite dust is inhaled, it can create significant health risks, including asbestos-related diseases.
__________________
Check out my pictures here:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


If at first you don't succeed... Skydiving isn't for you.
Reply With Quote
  #3  
Old 08-17-2009, 10:42 PM
Apprentice
 
Join Date: Jul 2009
Location: Cochrane, Alberta
Posts: 104
Default Re: Insulated Hearth

Zonolite as manufactured and sold today contains no asbestos. It would be illegal to sell. In fact, I asked that question as I remember the Zonolite of old and remember the ads on TV for attic fill. I also remember the class action lawsuits that settled for big bucks.
As an insulative material only, it should be fine and is commonly used. ...but my question remains, can or should I use it for the insulative hearth?
Reply With Quote
  #4  
Old 08-18-2009, 01:52 PM
cynon767's Avatar
Apprentice
 
Join Date: Dec 2008
Location: Sacramento, California
Posts: 230
Default Re: Insulated Hearth

I would imagine that whatever it is coated with would make it hard to bond with the cement, leaving the insulation too loose to support the dome. IIRC, there was some issue with silicone-impregnated vermiculite mentioned in the FB plans. Whatever the chemical agent, I would worry about it reacting at temperature.
__________________
-jamie


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
chimney vent and insulated hearth issues mnpdryer Newbie Forum 0 06-19-2009 12:06 PM
Insulated Hearth Question jcg31 Newbie Forum 7 09-29-2007 08:03 AM
Between Hearth SLAB and Hearth BRICKS, slip plane. Marcel Newbie Forum 2 09-12-2005 06:35 PM
Spanning the wood storage below the Hearth slab. Marcel Getting Started 0 08-22-2005 10:13 PM
Insulated Hearth Howie Modular Refractory Oven Installation 5 08-11-2005 06:56 PM


All times are GMT -7. The time now is 07:23 AM.

Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
© 2006/10 Forno Bravo, LLC