Earth oven

[Clara]

Hoping to build an earth oven in the next few weeks (hmmmm pizza!)

I´ve read the really comprehensive article linked to on the site, but I was wondering if anyone had any tips from personal experience to share....

Clara x.

[Cheezy]

all I know is that you have to let them dry out very slowly (abit like plaster etc.) to try to prevent as many cracks as posible forming

[eek]

I tried one, not very successfully. I have all sand and you need good clay for it to work. I ended up raiding some construction sites where there were piles of clay soil. I had a problem getting the right consistency and still it cracked. If you can find this book it is a great source.


Build Your Own Earth Oven by Kiko Denzer

New Edition, expanded to 100 pages, color photos! Build Your Own Earth Oven is a fully-illustrated handbook for making a simple, wood-fired, masonry-style oven. It provides clear, step-by-step instructions for building and firing the oven, as well as complete directions for making sourdough bread in the best (and simplest) artisan tradition.

Earth ovens are far more simple but every bit as effective as a fancy brick hearth or modern, steam-injected commercial oven. The dense, three-to-twelve inch thick earthen walls store the heat of the fire; after the hot coals are removed, the hot walls radiate a steady, intense heat for hours. The resulting steamy environment is essential for the crisp, flavorful crusts of true hearth loaves, and you can easily build it for less than the price of a couple of fancy dough-rising baskets!

Building with earth is safe, easy, inexpensive, and practical. Good building soil is usually right under your feet! Use it plain, or mixed with sand and straw. Build the simplest oven in a day! Adding a roof and foundation makes it permanent. The simple, round shape makes a beautiful garden sculpture, or can be sculpted into a fire-breathing dragon!

Illustrated by the author with over a hundred drawings and photos, it includes inspiring color pictures of sculpted ovens and their builders, as well as further references on food, baking, and building.

About the Author Kiko Denzer is an artist, writer, builder, and baker who has been working with earth since 1994. He is also the author of Dig Your Hands in the Dirt: A Manual for Making Art out of Earth, and other titlesImagine a huge Phoenix bird, its belly the oven, the flue its throat, with smoke escaping from the upturned beak! Children can help build these ovens, and play with earth at the same time.

[Clara]

Thanks. It´s the same author for the article on the website I think.

I was hoping that the clay from the bed of a nearby stream would do it, it´s the same stuff that is used traditionally here for covering roofs.

Was it solely the material that made yours not turn out so well or were there other problems?

Clara x.

[Jack]

Gidday

I too am thinking about making one. A while ago I did a bit of searchin around the net and got these:-

http://bensart1.homestead.com/breadovens.html

http://heatkit.com/html/bakeoven.htm

I sorta favour the first one most and will just use whatever I walk around on here.

[Muddypause]

Dunno if it'll help any, but there's another article by Kiko Denzer here, from the archive of Permaculture Magazine.

I also notice that Lower Shaw Farm have a weekend course planned in June.

Clara, can you point to the link you first mentioned - I can't seem to find it on the site. Maybe it's the same as the link above. Be interested to see it, though.

[eek]

I could not get the consistency right in the mix. I did it twice, one time with my BIL who is a contractor, and still major cracks. The rim we sculpted for the door fell right off when it dried.

The actual shell is still sitting on the foundation, but the hay/straw has come through the mud as it settled. I let it dry slowly, tarped it, etc. but no go. I will probably try again this summer as I really want to be able to cook outside without paying rediculous amounts of money for materials and/or labor.

Good luck with yours, keep us posted.

[Wombat]

Yep, I made one during our winter and the process (based on Denzers' book) worked very well. Unfortunatley on a test firing it got nowhere near close to hot enough to cook pizza. I am going to install a chimney at the rear and have another go..............................soon!

Nev

[the.fee.fairy]

There was one at Big green gathering that looked like a lizard...very cool it was too!

Might have a go at this in the summer! Got to be something useful to do with the clay soil!

[Clara]

Work in progress.... two brave canadian wwoofers braving the snow....very exciting.

Clara x.

[Karen_Grace]

Hi Clara

How did you get on? I'm a potter, but have never used clay in this way so I'm finding this interesting.

I would have thought that soil mixed with clay would weaken its structure.
Sand makes it less likely to shrink on drying so less likely to crack.

If air gets trapped inside the clay it can't escape while the clay shrinks, the pressure builds up and a crack forms. If the clay is heated up with a bubble of air inside you have a potential bomb.

Generaly, if the clay is more than about an inch in thickness it will crack because the water inside cant escape thats why straw is added to bricks so that when they are fired there are channels for the water vapour to escape.

[Clara]

That´s interesting. I am indeed cracking up!

The clay was from the land and so has quite a lot of small stones in it.

Making bread ovens with the local clay is traditional here, my neighbours tell me to just keep filling the cracks as they appear.

though I have thought about cheating and asking a local potter for some of his terracotta clay to give it another layer - what do you think?

I have yet to fire it up, but will let you know how it goes when I get ´round to it. I don´t think it will explode as we made it the way Kiko Denzer describes, and he doesn´t mention this as a problem

clara x.

[Karen_Grace]

As long as it holds together you will probably be ok. If you are going to fill the cracks do it before you fire it up. When the clay gets hot chemically combined water is driven off and the pot won't combine with the raw clay. Its a bit like trying to join a mud clay handle onto a teracotta plant pot.

The clay will shrink again when it gets hot. I dont know how it will cope with the stones since they won't shrink, but if people have done it before in that area you may be ok.

If it doesn't work, dont give up. Your local clay can easily be procesed to remove stones etc.

Adding an extra layer probably won't help. The first lot will already have shrunk, another layer will just shrink and crack off. Better to wet the cracks really well so that they can accomodate more wet clay and just fill them in.
Good luck

[duncang]

Evening all!!

For those who might still be watching this thread, I have built my own, and it captivated me so much I have been planning to open a small artisan bakery for the last year or so and things are just starting to take shape.
I learnt everything I know from a book, but since experimented a fair bit, so there's some info that might be of us on my page here.

Best of luck to anyone having a go, I loved it!!!
Duncan

[growingthings]

duncang

the page is fab , I don't think that I have got room at home for one, but the thought of one down the plot to complement the bonfire parties is a very tempting one.

cheers