Leaning toward a clay/cob/earthen oven

[ronzorelli]

For those who don't know... which is probably everyone because I don't remember ever sharing it here on the forum, we're moving to a new house soon.

At the new house, Ronzorelli will have the room in the back yard to build himself a WFO. Ronzorelli is VERY excited and happy about the very thought of this. Ronzorelli doesn't normally talk about himself in the third person so Ronzorelli doesn't know why exactly he's doing it now... so Ronzorelli will stop.

Seriously, I'm jumping for joy inside like... a little girl? Ok, maybe a little boy who just got the present he'd been wanting for years. I've dreamt about building one for years. I finally get the chance to do it...

Now... again... for those who don't know, I'm one cheap and LAZY... SOB. I don't want to work too hard and I don't want the job to take too long, and I don't want it to be remotely even close to being expensive... for those reasons, I'm leaning toward the earthen WFO spectrum.

I haven't seen a lot of resources on here about the earthen oven types, which is understandable considering it's mainly for Forno Bravo type brick ovens.. I've done some research on line and I'm looking to buy "Build Your Own Earth Oven" eventually before we move.

With all that said, I'm ALWAYS open for other advice, hints, or tips from anyone who's done it themselves.

So... anyone have any advice?

[dmun]

Re: Leaning toward a clay/cob/earthen oven

There's a lot here about cob ovens, though it's a bit outside my source of expertise. I think in general, if you have to buy pottery clay, it's more cost effective to build with firebrick (in the states) If you're disinclined towards backbreaking work, then maybe mining and processing your own clay isn't the route to go.

[mklingles]

Re: Leaning toward a clay/cob/earthen oven

Depending on where you live "mining and processing your own clay" just means digging up some dirt. In Portland Oregon, people just dig up the local dirt add some sand. With that mix they build successful ovens. This book: Build Your Own Earth Oven, 3rd Edition: A Low-Cost Wood-Fired Mud Oven; Simple Sourdough Bread; Perfect Loaves; by Kiko Denzer and Hannah Field provides some specific tests you can perform in your kitchen on the dirt in you back yard to determine if it is good for making an oven.

[Tman1]

Re: Leaning toward a clay/cob/earthen oven

Why so gung-ho on earth/cob/clay oven and not brick?

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

Why so gung-ho on earth/cob/clay oven and not brick?

I laid that out already... in the first post.

I don't have the brick laying skills to do something like a domed brick oven.

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

If you're disinclined towards backbreaking work, then maybe mining and processing your own clay isn't the route to go.

Um... mining and processing? You mean digging up a few shovelfuls? I'm not going to be renting a backhoe or digging for gold or anything. I'm just going to be digging up some clay.

[Tman1]

Re: Leaning toward a clay/cob/earthen oven

I laid that out already... in the first post.

I don't have the brick laying skills to do something like a domed brick oven.

Well, I think 95% of the people on this forum who've done a pompeii style oven didn't think they had the skills either.

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

Well, I think 95% of the people on this forum who've done a pompeii style oven didn't think they had the skills either.

I'm also not willing to go out and buy tools to cut and lay brick that I will never use again.

I'd rather simply form the dome with my hands.

[mklingles]

Re: Leaning toward a clay/cob/earthen oven

I started with the intent to build a mud oven. I believe the mud oven can be built less expensively. However then it is all mud and cob. That must be kept dry. Once you add in enough structure to keep a cob oven dry and happy then your starting to get towards the cost of a brick oven.

So, it depends on your location (wet / dry), your desire for a permanent oven or a temporary one. Here temporary for mud/cob might mean a few to 10 years, where a brick oven should out last you and probably your children.

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

I started with the intent to build a mud oven. I believe the mud oven can be built less expensively. However then it is all mud and cob. That must be kept dry. Once you add in enough structure to keep a cob oven dry and happy then your starting to get towards the cost of a brick oven.

So, it depends on your location (wet / dry), your desire for a permanent oven or a temporary one. Here temporary for mud/cob might mean a few to 10 years, where a brick oven should out last you and probably your children.

You may have a point with that added cost... that's definitely something to be factored in.

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

So... I clearly have more contemplation on this to do then...

Shame on me for jumping to conclusions without enough thought...

[dmun]

Re: Leaning toward a clay/cob/earthen oven

You mean digging up a few shovelfuls? I'm not going to be renting a backhoe or digging for gold or anything. I'm just going to be digging up some clay.

A few shovelfuls? A 36" pompeii weighs about 1500 pounds, and that's dry. Water's heavy, and will nearly double that weight. Now I've read here that mushing the straw into the clay with your feet is a lot of fun for the whole family, but I guess it depends on what you consider fun

[azpizzanut]

Re: Leaning toward a clay/cob/earthen oven

Hi Ronzorelli,

My first oven was a kit bundle (parts, mortar, firebricks, chimney, insulation) from a company in Ohio that was available through a dealer here in Arizona. I thought it would be easier than building a Pompeii style oven with half fire bricks and mortar. My second oven IS a 36" Pompeii style oven and now that I am nearly finished with it I can tell you with some expertise that it is only marginally more difficult to build.

Much of the effort building an oven is with the non-oven parts such as the base and stand. Both of my ovens have similar sized bases and stands. The mixing and handling of cement, mortar, re-bar, brick and block is about the same whichever way you go. The only easy part was that the kit oven had only eight parts, but they still had to be mortared in place then covered with refractory insulation then Portland/perlite insulation to form a dome. I made an enclosure for it and tiled the entrance. Lots of work.

Now that I've been working on the Pompeii I can say it is slightly more difficult but much more satisfying. Each row of bricks is a goal to accomplish. I consider the first oven a training exercise that gave me skills, experience and confidence. Would I ever consider a kit bundle oven again in the future? Sure I would. When you are done with either type you know you have expended serious amounts of time and labor. Do some research on kit ovens in your area and shop around. Also, download the free Pompeii oven plans and look them over to get an idea of the steps involved in building an oven. These ideas may give you some options to a cob oven. Best of luck.

Cheers,

[ronzorelli]

Re: Leaning toward a clay/cob/earthen oven

Thanks for your kind and informative reply, Bob.

I've got a lot to think about... not something I want to rush into and blow it... and waste my time and money.

Thanks again.

[Rocko Bonaparte]

Re: Leaning toward a clay/cob/earthen oven

If you start with a strong, stable foundation, you can pause to think about what you want to put on top of it.

I was afraid to work with brick too so I went with a cob route. I had to buy clay and good sand to mix with it. I should probably check receipts for you, but I think it was about $150 for all that. But that would easily be 100 firebricks and maybe the appropriate mortar too. There's a chance the prices would equalize, though likely brick would only be marginally more expensive even factoring in some beater brick cutting saw.

It was probably a lot easier to do though, but I wouldn't say brick is impossible. After I got comfortable making something out of cinder blocks, I got a lot less scared doing masonry stuff. Actually now I would prefer doing masonry over doing, say, carpentry. I just find it more fun.