Forno Bravo Forum: The Wood-Fired Oven Community

Forno Bravo Forum: The Wood-Fired Oven Community (
-   Getting Started (
-   -   How many bags of vermiculite (

Art nj 03-03-2014 04:26 PM

How many bags of vermiculite
I'm in the gathering stage of my barrel vault oven, and have a question on the amount of 4cu ft bags of vermiculite everyone used on their ovens. I plan on a 4" slab of vermacrete under the 32"x36" oven, plus insulating with loose vermiculite on top an the sides.
I was planning on getting 2 bags of medium #2 and 2 bags of course # 4. I'm just not sure if this is gonna be to much or not even close to enough.


Les 03-03-2014 06:02 PM

Re: How many bags of vermiculite
You will never have to much (within reason) Are you building an enclosure around it and loose fill?

jeeppiper 03-04-2014 09:46 AM

Re: How many bags of vermiculite
I ddin't use any vermiculite. I opted to use extra silicon fiber blanket instead. My fear was that small gust of wind while I was buttoning up my oven, and I would have vermiculte pellets floating around the yard forever.

Art nj 03-04-2014 10:36 AM

Re: How many bags of vermiculite
Thanks jeeppiper, that's what I may actually do.. Just buy ceramic fiber board for under the floor, and blanket on top ,back and sides of the oven.

jeeppiper 03-04-2014 01:46 PM

Re: How many bags of vermiculite
My thought was that if I ever had to go in and repair the dome, I didn't want to have to deal with pulling out all of the loose vermiculite. Why are you doing the barrel vault instead of the Pompeii dome? most folks on this forum prefer the dome over the barrel.

Art nj 03-04-2014 02:52 PM

Re: How many bags of vermiculite
I plan on baking bread and other foods more than pizza, and i like the idea of more retained heat.The build is similar enough between the both types, but I'm not doing it exactly like the Alan Scott design. I have the book bread builders and have been studying it, just gonna "modify" mine a bit. Probably just changing the insulation from under the concrete base to on top of it. My dimentions are pretty close : 32" wide on the inside- 36" deep and a dome height of 18". My original form that I shitcanned was 30"w ,36"L, and a dome height of 32". I thought that it was a little to high of a dome so I "sqooshed" it down and made it a bit wider and a little lower. Do these numbers sound right you think?


Art nj 03-04-2014 03:00 PM

Re: How many bags of vermiculite
I also had an idea I like to see what others thought... I work with a lot of sheet metal in my business (signs), and was thinking of putting a sheet of bare aluminum between the insulating layer below the firebrick floor and the concrete as a break. I may actually be able to bend a pan to make an air gap between the layers. The more I think about it the more I think I'm gonna try it, maybe put holes in it in case of water intrusion, if I do bend a pan, it'll obviously need bracing inside. I'll see if I could come up with something and I'll post a picture.


boerwarrior 03-05-2014 07:12 AM

Re: How many bags of vermiculite

you are going to need better insulation than a sheet of aluminum under the firebrick... In an earlier post you said you were going to use CF. Did you change your mind?

Art nj 03-05-2014 08:44 AM

Re: How many bags of vermiculite
I said between the insulation layer and the concrete base... I'm probably going with ceramic fiber board under the firebrick floor.

boerwarrior 03-05-2014 09:55 AM

Re: How many bags of vermiculite
My apologies! I read too fast!

Just remember that there will be a lot of weight on the floor so if you have an air gap with bracing makes sure it can take the weight without flexing the ceramic fiber board

All times are GMT -7. The time now is 06:25 PM.

Powered by vBulletin® Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
2006/10 Forno Bravo, LLC