web analytics
sawdust vs. vermiculite insulation - Forno Bravo Forum: The Wood-Fired Oven Community



New Forno Bravo Forum Feature

Forno Bravo Forum Community,

You will notice a new forum at the top of the main page called, "Ask Me Anything". This forum will be used for live one hour "Ask Me Anything" (AMA) sessions hosted by people who are knowledgeable in different areas pertaining to wood fired ovens. How it works:
- Each AMA will have a "sticky" thread where the community can post questions they would like answered during the live session. This will allow everyone to participate even if you can't be online for the live session. These questions will not be answered by the host until the live AMA; if you need an answer quickly, you should post it in the appropriate Forum area for the community to respond.
- Another thread will be posted for the live AMA. Registered users who are logged in during the live session can interact with the host by asking questions and receiving responses.
- The live thread will remain in the AMA forum to view after the session.

To kick off our AMA feature, we have invited author, chef and master bread maker and host of Pizza Quest, Peter Reinhart, to be our first host! Peter will be in the Forum on Monday, February 15th, from 7:00 - 8:00 pm EST. If you are unable to be online during the live session, you can post your questions in the sticky post. Peter will answer those questions during the live session on February 15th. You can view Peter's answers to your questions as well as what happened during the live session in the session thread.

We hope you enjoy this new feature! Please let us know if there is a topic that you'd like to have as an AMA and we'll look for a host!

Forno Bravo
See more
See less

sawdust vs. vermiculite insulation

  • Filter
  • Time
  • Show
Clear All
new posts

  • sawdust vs. vermiculite insulation

    hey oven, pizza, bread, building lovers. i hail from the olympic peninsula in washington.

    i have taken part in building 3 cob ovens at this point, enjoyed baking in all but have been disappointed in their ability to hold heat, especially in the 475 degree range.

    i have just finished building a 27 by 32 oven and recently got a lot of small wood chip/sawdust material. i was planning on doing 6 inches of insulation with the chip sawdust and clay but i am beginning to think i might be much better off with vermiculite. i insulated the hearth with vermiculite portland and layer of 3 1/2 inch bottles on their side.

    the sawdust was free but im thinking i might want to just spend the extra for a better insulator. thanks.


  • #2
    Re: sawdust vs. vermiculite insulation

    You could keep a book to take bets on the sawdust catching fire before rotting.


    • #3
      Re: sawdust vs. vermiculite insulation

      thanks for your friendly advice. just trying to keep it cheap and stay out of the hardware store.


      • #4
        Re: sawdust vs. vermiculite insulation

        Kiln builders often use sawdust as an insulating material. They fire to temps way higher than we do. Maybe the sawdust burns, depending how close it is to the fire source and how high the temp goes, but what does it matter if it burns anyway, the result is a void which heat does not readily pass through.
        Kindled with zeal and fired with passion.


        • #5
          Re: sawdust vs. vermiculite insulation

          yeah, thats ultimately what you want. a friend recommended using straw which will do the same thing but provide more airspace, mix easier with the clay slip and be faster to apply.


          • #6
            Re: sawdust vs. vermiculite insulation

            Insulating firebrick voids are made with sawdust, but they are fired to a high enough temperature to completely burn the sawdust to create holes in the brick. Any plan which leaves the sawdust in contact with hot masonry is doomed to fail, imo.
            My geodesic oven project: part 1, part 2


            • #7
              Re: sawdust vs. vermiculite insulation

              "thanks for your friendly advice. just trying to keep it cheap and stay out of the hardware store."

              Vermiculite (or perlite) is not that expensive. Check with local plant nurseries.


              • #8
                Re: sawdust vs. vermiculite insulation

                on another thread someone mentioned McMaster-Carr as a source for Vermiculite. I needed some recently so I ordered a bag instead of driving all over town trying to get it from a nursery. IIRC, the 4 cubic foot bag was ~$30 including shipping and was on my doorstep in three days. Hard to beat that for easy, efficient and cheap.