KevinTV

Episode 41 – Cob Oven

05.09.12

Bricking Cob Oven FacadeFinally, a proper cob oven graces my back yard. I read Kiko Denzer‘s book years ago and was inspired by his ‘who needs expensive building materials‘ attitude. As you may know, I tend to dig frugal. He’s an advocate of using repurposed materials, and I’ll credit the base of my oven to him – it’s slabs of busted up sidewalk concrete saved from a city aggregate recycling yard. The rest of the face is bricks and cinders courtesy of kijiji. Aside from the hearth bricks, my cost on this build was roughly $30 for a load of sand and some incidentals. The hearth bricks could have been standard bricks, but I figured I use my oven more than most, so opted for a longer-lasting solution. The stand is mortared with cob [clay and sand], the facade a page from the Allan Scott book of wood-oven building. It was nearly annoyingly remarkably fun working with the mud. I’m sure I annoyed oven-building-friends Blair and David, to whom I owe many thanks, with my constant remarks about how fascinating it was to take such simple materials, and work them into something so damn cool. The video shows the step-by-step progress of the build. If you’re interested in the details, again, I’ll defer to Kiko’s book – but what I will tell you is that it was one of the more enjoyable, well-spent weekends I’ve had in a long time.

24 Responses

  1. Judy Z says:

    Cool! Pretty impressive to complete that in a weekend and your young helpers are adorable.
    Do you have a chimney? I couldn’t tell from the video.
    How long did you allow the clay to cure before you set the fire?

  2. Sherri says:

    Wicked awesome! :)

  3. Jeremy Calow says:

    That is proper awesome Kevin! Not to mention just plain gorgeous too… Nicely done!!

  4. becky3086 says:

    This, of course, is wonderful. (Could you send them to build me one?) I want one but have to collect up material for it but haven’t come across anything yet.

  5. Kevin says:

    Judy – yep, built a chimney. There’s a shot of it in construction phase, but you wouldn’t know unless you knew what you were looking at. It works BEAUTIFULLY. I’m so pleased with the chimney, as it’s a pleasure to work around rather than getting smoke and heat in your face. I’ll esp. love that in the heat of summer. I started increasingly hotter fires after a couple days of letting it cure. The mix was pretty dry, and we had the sand out of it immediately after the dome build – based on the philosophy that the clay needs to dry and shrink – both hindered by leaving the sand in.

    Sherry – thanks!

    Becky – it was such a fun build, I encourage everyone to try even a rudimentary one. Mine was more complicated because of the facade/chimney bricking, but the cob oven itself can be super simple. Hope you find some materials soon!

  6. Andrew Turner says:

    Fantastic!

  7. ashley says:

    Thanks for the inspiration- I’d like to build one of these one day!

  8. Todd says:

    SUPER SWEET Kevin !
    Still trying to source kiln / fire brick for lining mine with, AH CANNAE WAIT, thanks for providing some of the inspirado….

  9. Beth in Ky says:

    Love it! Did you hold your breath as you took out the sand, or were you sure it would not collapse@

  10. Barry Preuett says:

    Awesome Kevin! Question: Why the glass bottles?

  11. What a cool oven!!! And a fun time for all, I see . . . .

  12. Kevin says:

    Ashley – do!
    Todd – Alliance will sell you the bricks. Ask for Don. They also sell 12X18 tiles, if that makes sense for your design. I went with an extra brick in length and width than Kiko’s plans for a 27″ oven. So I guess mine’s 31.5″.
    Beth – a little bit, but the cob is so tough and strong, that I wasn’t tremendously worried. Took a bit out, and it seemed to not budge, so committed.
    Barry – poor man’s insulation. I’m using ceramic blanket for my big oven, but wanted to go simple and cheap on this one. Not my idea, seems to be the norm for hearth insulation out there for projects of this type.
    Sharon – indeed fun for all. Didn’t realized how much my kids were involved until I started editing!

  13. Alan says:

    Very Very cool!!!

  14. arlene says:

    That is beautiful! I’ve just read Kiko’s book through twice. Went out last weekend trying to access the river valley to find some good clay soil…no luck. I thought I’d mix a batch of test cob and do a mini oven as he suggests, just to get the feel of it. We will hopefully be building one this summer. No permit required, right? (it’s like a fire pit that way I assume…) And the proximity to the fence isn’t an issue? I’m planning one sans chimney, but yours is GORGEOUS! Thanks so much for the video inspiration and encouragement!

  15. Kevin says:

    Arlene – I got my clay from digging a hole in my back yard. Benefit was my hole was 17′ wide, so I could cherry pick the zone of the best clay. Let me know how your mini-oven goes. The building permit guy told me he’d built one before, and that there was no need for permit. Although I completely recommend you asking the city yourself, unlike a firepit which has to be 3m away from property line, structure, etc – an enclosed fireplace I believe has to be 1m. The chimney opening and oven door are over 1m away from the fence. I also recall a piece of the municipal bylaw that expressly excludes any device used for the cooking of food – again, recommend some non-light reading. As a point of reference, I’ve had far hotter bbq lids near a house than I have oven dome near a fence – so in that sense I’m way not concerned. The fire and sparking is also extremely well contained relative to something like a fire pit. When well insulated, an oven dome will keep snow atop it, even when the oven’s hot inside.

  16. eric says:

    so awesome. nice work. you’ve inspired me with this clip.
    e

  17. Cathy Walsh says:

    How interesting! If we were neighbours, I’d be hanging over the fence all time wondering what you’d be up to next. Looking forward to see what you cook/bake up in there.

  18. Michael Allen says:

    Top Shelf.

  19. pamela marriott says:

    so a couple of questions. what is with the wine bottles. how did you clean out the dome structure, is that regular clay that went around it? why plastic on the brick. i am still working on my husband to take on a wood fre oven and the pushing point that he loves that i can cook. so……. working on a greenhouse this year though.

  20. pamela marriott says:

    one more thing. where did you get the book you have referenced.

  21. Kevin says:

    Pamela – bottles = insulative air pockets below hearth bricks. cleaned out the sand by hand, mostly, with the odd help of a hoe. the clay was from my back yard, nothing special. plastic was to keep the hearth bricks as clean as possible – not worth the trouble. have fun with the greenhouse!

  22. Ed Murphy says:

    Fantastic video. I just built one myself, and found this particular page off of your Cob Oven Bacon page. Smoking in the oven is big on my list of things to try, as soon as mine is fully dry and a few batches of bread come out of it!

    Your front brickwork is far more beautiful than my simple, if somewhat irregular arch… yet another of the things I’d do differently if I was doing it again.

    So many things to try cooking, and I can’t wait!

  23. Neil says:

    How did you support the back section of the chimney? You have a lintel for the front but I am wondering how the back is supported? Is there another lintel or does the cob support the brick? I think it is fantastic and I am going to be building one soon but would like to have a chimney similar to how your design is. Please let me know. Thanks

  24. Kevin says:

    Hey Neil – good question. It was cobbed up from the dome in the back, but we don’t build them that way anymore. Plan to have a freestanding, double linteled chimney build. Hasn’t been a problem for the dome, but what happened on mine is as the dome shrunk as it cured, it lost some height on the back side – about a mm, creating a crack in the mortar on the front of my chimney. Not a big deal, but avoidable. Hope that helps!

Leave a Reply


seven − = 6