Outdoor Cob Oven

Building another and better outdoor cob oven

It’s been several years since we have been without an outdoor cob oven at our disposal, and I have dearly missed having it around! The original “$20 pizza oven” that we built back in 2009 had to be “moved” since it was in the way of drainage work that needed addressing around Gobcobatron.

But at last, the time has come. In the coming week or two, we intend to build another outdoor pizza oven, better than the last. The time, we have a proper shelter to shield it against the elements (see above!), and we’ll be making several other modifications for creating a lean, mean pizza baking machine. Er… it’s actually kinda big, and distinctly un-machine like, but whatever.

The Cob Oven: Revisited

In 2009, we opted for a 22.5″ diameter oven. Small, but respectable, and easily capable of cooking a lot of food for its size. This time, we are going to bump up the size just slightly to 27″, to allow for a litttttle more interior maneuvering space, and so that we can build a wider doorway to slide in pizzas. That does mean we need more foundation material, fire brick, and other materials, but it will be nice to have a slightly bigger oven for our workshops in September and October.

Other differences? We intend to better insulate the dome this time around, perhaps even doubling the amount of insulation. We may skip out on the sawdust/clay insulation mixture in favor of a straw/clay combo, which I suspect will be more insulative. It’s yet to be seen how easy it will be to apply such a loose mix to the earthen dome, however.

The first cob oven didn’t have many problems drafting, but we do want to design a chimney in this second iteration from the get-go. The front-mounted chimney will help with draft, and it will re-direct smoke above the shelter and hopefully out of our faces.

Finally, I was excited to learn about a “new” fermented clay plaster recipe this week. I don’t have the recipe memorized yet (nor do I have it copied down), but this has been one of the more exciting things I’ve heard about recently in the natural building realm. More on the particulars of that plaster later, but the oven will be a good first chance to try out the technique.

Keep posted for updates on the return of the outdoor cob oven!

p.s. We will again be referencing Kiko Denzer’s excellent book, Built Your Own Earthen Oven. Love that little book!

 

16 Comments

  • Nico Morris says:

    Hi I’m a Cob designer and artist you can see some of my work on my fb page

    I have some good suggestions for your oven design

    front chimney YES and you need a rear air hole fire oven with door shut

    fires twice as fast and clean!

    You can use RED LAVE Light slip mix as insulation works great or take straw turds(snakes worms whatever) Make Croissants out of them and stack them up over your high sand inner level WORKS GREAT done it you can lean your cheek against the oven at full heat.

    Do you know Michael Smiths trick for the inner sand level ?? if not ask him!
    and by all means look up “Grog” It’s a ceramic material you want to know about

    Yours freely Nico

  • Nico Morris says:

    Hi I’m a Cob designer and artist you can see some of my work on my fb page

    I have some good suggestions for your oven design

    front chimney YES and you need a rear air hole fire oven with door shut

    fires twice as fast and clean!

    You can use RED LAVE Light slip mix as insulation works great or take straw turds(snakes worms whatever) Make Croissants out of them and stack them up over your high sand inner level WORKS GREAT done it you can lean your cheek against the oven at full heat.

    Do you know Michael Smiths trick for the inner sand level ?? if not ask him!
    and by all means look up “Grog” It’s a ceramic material you want to know about

    Yours freely Nico

  • Nico Morris says:

    Lava that is

  • Nico Morris says:

    Lava that is

  • Trish says:

    Thanks for the correction Nico Morris.

  • Trish says:

    Thanks for the correction Nico Morris.

  • Trish says:

    Is that 27 inches in diameter for the outside measurement or the inside? What is the total flat cooking space of that. I was also curious if a 40 inch in diameter (for the inside cooking space) would be feasible. I am interested in making something for a small neighborhood. Thanks.

  • Trish says:

    Is that 27 inches in diameter for the outside measurement or the inside? What is the total flat cooking space of that. I was also curious if a 40 inch in diameter (for the inside cooking space) would be feasible. I am interested in making something for a small neighborhood. Thanks.

  • ziggy says:

    Trish: 27″ is the interior diameter. You can figure out the cooking area from there, but it’s big enough for two small pizzas, or 3 loaves of bread, I think.

    • Trish says:

      Thanks Ziggy. I think for a small neighborhood or something similar I would have to build something a little bigger. 🙂

      • ziggy says:

        Agreed. It would be awesome to have a communal bake day where folks can bring their dough to bake, just like the old traditions… and throw a good, big pizza party in there, too.

  • ziggy says:

    Trish: 27″ is the interior diameter. You can figure out the cooking area from there, but it’s big enough for two small pizzas, or 3 loaves of bread, I think.

    • Trish says:

      Thanks Ziggy. I think for a small neighborhood or something similar I would have to build something a little bigger. 🙂

      • ziggy says:

        Agreed. It would be awesome to have a communal bake day where folks can bring their dough to bake, just like the old traditions… and throw a good, big pizza party in there, too.