#1  
Old 11-07-2009, 03:01 AM
Serf
 
Join Date: Nov 2009
Location: Australia
Posts: 8
Default Insulation Advice

Hi, I have purchased a woodfired oven Kit made from high density castable refractory concrete. The kit comes with a 1 inch Fire Blanket for the floor and a 1 inch fire blanket for insulating the dome.

The manufacturer swears black and blue that this is enough insulation and I have seen heaps of pictures of completed ones.

What are your thoughts?

Basically if i follow the instructions i will be doing a concrete slab with a fire blanket and then laying the floor on top of this.

I will be covering the dome in a 1 inch fire blanket (chicken wire, alfoil etc) and then rendering it.

Is this enough insulation? What do yo recommend?

Many Thanks. This is a brilliant forum.
Reply With Quote
  #2  
Old 11-10-2009, 04:22 AM
Apprentice
 
Join Date: May 2009
Location: Austin, Texas
Posts: 102
Default Re: Insulation Advice

I find it hard to believe 1 inch of anything is enough unless the actual dome itself is very thick. I built my dome according to the plans on this site, that produced a dome with a wall thickness of about 4.5 inches, I added 4 layers of the FB blanket and my stucco exterior has never gotten much above outside ambient air temperature. Fact is, more insulation means better warm up and longer sustained/retained heat which means it requires less fuel.
Reply With Quote
  #3  
Old 11-10-2009, 05:24 AM
dmun's Avatar
Moderator
 
Join Date: Jul 2005
Location: New Jersey USA
Posts: 4,216
Default Re: Insulation Advice

I'm particularly concerned about the "blanket" under the floor. I suspect it will compress and loose all insulation value. We use a rigid insulation, either four inches of vermiculite concrete or two inches of rigid refractory board under the floor.

As DimTex says, an inch of anything isn't enough. You'll have trouble getting it up to temperature, and keeping it there. I suspect that your vendor is trying to save money at your expense: Refractory insulation is very expensive, particularly down under. I wonder what other ways he's saving money?
__________________
My geodesic oven project:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #4  
Old 11-10-2009, 02:14 PM
Serf
 
Join Date: Nov 2009
Location: Australia
Posts: 8
Default Re: Insulation Advice

Thanks guys, this is what I suspected. I am making provisions and buying insulation bricks for the floor. They are 63mm thick and are apparently better than using vermiculite or hebel. At $1.80AU each brick they better be.

I have ordered a roll of fire blanket which will give me 3-4 inch of blanket around the outside of the oven.

This will add about $250AU to the cost of the project.

I have spoken to others who use this oven and they have said it works perfectly but the oven is roaring hot all over and cant be touched and they go through loads of wood for each cooking session.

Hopefully the extra insulation will alleviate this issue.
Reply With Quote
  #5  
Old 11-10-2009, 02:57 PM
james's Avatar
Brick Oven Merchant
 
Join Date: Mar 2005
Location: Pebble Beach, CA
Posts: 4,648
Default Re: Insulation Advice

I want to second the advice to not use the blanket under the floor. I have seen that technique, and as you have noted -- the outside and bottom of the oven get hotter than heck when you are cooking. That isn't good for making pizza, wood consumption, or retained heat roasting and baking -- or for your neighbor who burns his hand.

Insulating firebrick below is OK, and 3-4" of blanket on top is the way to go. You will be glad you did it.

James
__________________

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


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
Securing & Shaping Wire Mesh Over Insulation WaWaZat Getting Started 9 10-30-2009 05:50 PM
Blanket Insulation altamont Pompeii Oven Construction 12 10-01-2009 09:09 AM
How far (laterally) should hearth insulation extend? kebwi Tools, Tips and Techniques 2 09-29-2009 11:22 AM
Oven Insulation Naushad Kasmani Commercial Pizza Ovens 6 08-24-2009 12:05 PM
insulation retrofit for pizza oven munderseth Getting Started 12 01-28-2009 10:39 PM


All times are GMT -7. The time now is 08:56 PM.

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