web analytics
FB Board under floor AND dome? - Forno Bravo Forum: The Wood-Fired Oven Community


1 of 2 < >


Hello, Forno Bravo Community Forum members.

As many may have noticed already, the Community Forum site was briefly down today. While working on scheduled routine maintenance, we encountered an error when trying to add a software update. As the site is now back up and running, some of you may notice that some recent data has been misplaced from November 10th up to today. We are currently working on resolving the issue. The forum has full operational capabilities and we encourage all forum members to continue actively posting in the threads.

We apologize for any inconvenience that this issue may have caused you. The Forno Bravo family values each and every member of our community. If you have any issues or concerns, please feel free to let us know on our issues thread here:


Thank you for understanding.
2 of 2 < >

Forno Bravo Forum Thread Message

Hello, Forno Bravo Community Forum Members!

The Forno Bravo team has heard the feedback in regards to the community forum. We wanted to take the time to re-enforce our commitment to a fully engaged Forum with professional moderation.

Our top priority as a company is to fix all forum errors and issues that you are experiencing. As we are swiftly working on these problems, we want to say that we highly value the Forum Bravo Community Forum and every single community forum member.

We have set up this thread so that every member can address any concerns, issues and questions about the forum. Please feel free to ask whatever you would like in regards to the forum; let us know what issues you are experiencing so we can work on resolving them as fast as possible. However, we stress that we would like constructive engagement, so please be specific about the issue you are experiencing.

Thank you for all of your patience and continued support.

Link to topic: http://www.fornobravo.com/community/...with-new-forum
See more
See less

FB Board under floor AND dome?

  • Filter
  • Time
  • Show
Clear All
new posts

  • FB Board under floor AND dome?

    I just received my FB board and I am ready to build my Pompeii oven, finally.

    However, the FB board seems softer than I expected. I am not sure that this material will support the weight of the dome and the vent. Maybe it is only supposed to be under the floor and the dome rests on the concrete foundation.

    Any insight would help, I am ready to go if I can figure this out...

  • #2
    Re: FB Board under floor AND dome?

    The board can support the weight. You need the dome insulated from the hearth. When you say softer, what exactly do you mean? In no way is the stuff like concrete but it should be fairly firm.
    Check out my pictures here:

    If at first you don't succeed... Skydiving isn't for you.


    • #3
      Re: FB Board under floor AND dome?

      By soft I meant that my finger can leave an imprint. I did not expect it to be like concrete. Not exactly sure what I expected, but the dome will probably weight a half ton or so and all that weight will be on the 4 1/8" ring of my fire brick. Just didn't seem logical to me.

      Did you use FB board without any issues?


      • #4
        Re: FB Board under floor AND dome?

        The board you got will be fine. I'm sure the FB folks would not send out an unsuitable product. Yes, the board will seem too soft to support the entire weight of your oven, but this is a common perception. Just make sure you don't let any portion of your dome (and entry) come into direct contact with anything other than insulation. Any contact will cause heavy losses of heat through conduction which translates into excessive wood requirements during heat-up and rapid loss of residual heat.


        • #5
          Re: FB Board under floor AND dome?

          I thought that contact with the concrete might act as a "thermal short", but I was more worried about the weight.

          Since it looks like its OK I will proceed. Thanks

          When you lay down the FB board should you level with sand or fire clay?
          Maybe the bricks should be leveled on top of the FB board?

          I noticed that the fire brick thickness seems to vary enough to show lips...


          • #6
            Re: FB Board under floor AND dome?

            The recommended solution is to level the bricks on the board with a 50/50 blend of fine sand and fireclay, although there's nothing that says you couldn't fill voids between the board and your concrete suppoort slab with the mix as well.

            You can mix water with the blend and (notched) trowel it on wet or do what I did: just trowel on dry and tap the bricks with a hammer until you're satisfied. If you wet the bricks from the top it will set your 'mortar' underneath.

            You may want to level your floor bricks with a slight slope towards the entryway so if any water gets in it will run out.


            • #7
              Re: FB Board under floor AND dome?

              Thanks for the pointer Gianni.

              I'll see how much flex the FB board has when I lay it down and then I can determine if I need to level underneath it. Since I will be using the FB board I'll probably mix in very little water as to not saturate the board. Just enough to get the mix to flow.

              I've spent years thinking about this build and just as many getting my site ready. Now that I am finally at the point where I can build my dome I don't want to leave anything to chance.

              Wish me luck