web analytics
Sandstone harth? - Forno Bravo Forum: The Wood-Fired Oven Community

Announcement

Collapse

I'm Peter Reinhart! Ask Me Anything! Monday, February 15, 2016 7:00-8:00 pm EST

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.

Ask Me Anything New Forum Feature

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.

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

Sandstone harth?

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Sandstone harth?

    My uncle in south western Colorado wants to instal a modular oven using sandstone as his harth. Is that material ok for that aplication?

  • #2
    i'm no expert on sandstone but all of the the sandstone that i've seen were very weak aggregates. most pieces could be broken by hand. i don't think this would be a very good material for a hearth unless fully supported from beneath. from a heat retention/insulation standpoint it would probably be similar to sand. there have been several threads which have discussed the thermal characteristics of sand and i think the consensus was poor insulation but good heat storage.
    my site for our pompeii and tandoor ovens
    www.killdawabbit.com

    Comment


    • #3
      One of the theories behind the use of precast refractory floors (and brick) is that they have the right mineral composites to get/stay hot, and that they are porous, so they can extract moisture from dough and convert it into steam. If the floor is too hard or solid, it can't do that.

      I have to guess that is would also crack.

      Alf, are you out there? What do you think?

      James
      Pizza Ovens
      Outdoor Fireplaces

      Comment


      • #4
        Clarifacation

        James,
        I think he would put the precast cooking surface on the sandstone instead of cement. I really wanted to know if the layer of insulative cement between the sandstone and cooking surface is needed. I guess I was not very clear.

        Comment


        • #5
          I see. (I'm being thick).

          You will want an insulation layer somewhere in the hearth to keep heat from leaking down. I talked with a builder the other day who build a commercial oven on a 6" concrete hearth, and could feel the bottom of the hearth getting hot to the touch while cooking. His oven was cooling down too fast and his wood costs were higher than he had predicted.

          You can insulate directly under the cooking floor in you are only doing pizza and light baking. Otherwise, you would want to insulate under the sandstone hearth to keep the cooking floor and sandstone hot.

          Does that make sense?

          Jerald, what is the logic behind using sandstone in the hearth?

          James
          Pizza Ovens
          Outdoor Fireplaces

          Comment


          • #6
            Hi Jerald,

            If I have got your question right your uncle is using the sandstone hearth as the support for the oven floor. A couple of questions first as to the ovens use. What does your uncle want to cook / bake / roast in the oven? This will make a difference as to the amount of thermal mass under the oven-cooking floor.

            As to James question, sandstone is a very porous soft stone with large particles of sand making up the sandstone often with air gaps between the particles (thus making it good at water retention). Generally, unless you like a crunchy silica loaf I wouldn’t use it for an oven-baking floor.

            Sand has several interesting characteristics One: it conducts and holds heat well Two: it is flexible and can move with expansion and contraction. Three: Before we had our modern day insulating materials it was a reasonable insulator (however, not as good as charcoal)

            Alf
            http://www.fornobravo.co.uk/index.html

            Comment

            Working...
            X