Saturday, May 15, 2010

from Bread Earth and Fire (The Earth Oven)

 baking in the rain
The Earth Oven (con't)
Let’s assume the oven you’re going to construct will be for home use, and you are definitely not going to operate a bakery. If you construct a very large oven, it will be a waste of space, materials, and use too much firewood to heat up. A large oven will also take longer to build and contribute unnecessarily to global degradation. You won’t need the Taj Mahal of ovens. However, an oven that’s too small will be difficult to maneuver pizzas and breads. The Meaders decided on a circular oven with a 22.5-inch floor diameter.
For the purposes of this book, when I refer to the floor, hearth or deck, I am referring to the same place. It is there where your breads sit to bake.
We felt this would be a good size for pizzas as well as breads, but I don’t think you should build anything smaller than this. An oven this size will easily bake four loaves of bread or one or two pizzas at a time, although I personally like baking one pizza at a time. Baking pizzas and breads are always done separately. A pizza should take less than three minutes to cook, and with some help, you can crank out enough pizzas so your garden party of twenty folks will have no reason to complain.
Now we were ready to come up with a supply list, but when you do your oven, it’s not necessary to have all the materials on hand, although it does help.
You can buy most of the materials you’ll need at Big Box, but they won’t have clay, perlite, firebricks, straw, and sawdust. The firebricks are easily found at a masonry supply store. The Perlite and straw you will find at a garden supply store, and the sawdust you can get free from someone who does woodworking. You might find Perlite at big box, but if you do, it will probably be packaged in small bags, and it will be very expensive. It will be much more economical to buy Perlite in large bags. Vermiculite is a similar insulator, and if you can’t find Perlite, than use vermiculite; they are quite similar. Clay can be dug for free if you know where to look, or it can be purchased from a pottery supply store...
to be continued

Wednesday, May 12, 2010

from Bread Earth and Fire (The Earth Oven)

     The Earth Oven
 
     Abbott, aged 72 is an artist, 16 mm filmmaker and art professor. Nancy, aged 70 is a potter and French teacher. Working with them was a rewarding experience for me. They really are living proof that numbers don’t add up to anything. Senior citizens? What’s that? None around here. And there were no testosterone-charged young men to move 80 pound bags of concrete mix (although that would have helped), nor did anyone help them get the rocks up the hill to the building site. They did it all themselves with just a little help from me, and they celebrated their 50th wedding anniversary in 2008.      Every step in the process, every peek around the corner was an adventure for them because they had never done this before. “Please don’t do anything until I get back,” was a common refrain if someone had to run an errand. When the job was finished and the first rustic pizza was taken from the blazing oven, we all had to laugh considering what everyone went through to get to that final stage, but of course it was all worth it.      After the initial decision had been made to construct an earth oven, they had to decide where it should go. The size of the footprint is not really that much different between a small and large oven so the choice of location will remain the same. We’ll only be talking about outdoor locations because constructing an oven indoors poses some challenges that are beyond the scope of this book. Abbott and Nancy wanted an oven that would be close to their home, visible from the deck, but not pose a fire hazard. Although the oven would be raised off the ground, we still wanted to find a well-drained location because here in New England, frost in the ground could cause the oven to heave up in the spring and create some real problems, such as cracking and shifting the oven off level. Even after finding what we felt would be the best location, we would still dig down below grade for as least one foot and fill the space with gravel.
     The theory was that if any water did get in under the oven, the gravel would allow it to drain, and there would be no or very little freezing under the oven. If you were totally fanatical about preventing frost problems, then you would have to dig a hole about two feet deep, fill it with gravel and then lay in rigid foam insulation that extended six inches beyond the perimeter of the oven base. A slab would then be poured right on the foam. Or you could excavate a hole below the frost line that could be four feet deep and fill that with gravel. There was no way we would follow these alternative paths. We were willing to take our chances with the least demanding approach, and you should be able to as well. We simply dug a hole, filled it with gravel and then poured our slab.

That said, to really cover all your bases, I think it would be a good idea to get some advice from a local masonry contractor. Simply visit a masonry supply store and inquire. From my experience, folks really want to help out. Have a photo of the type of oven you’re planning to build so the person you’re talking to can relate it to your project.      If you are fortunate enough to live in an area where the ground does not freeze, is solid and has good drainage, then all you’ll have to do is level the surface and pour your pad, but more about that later. In fact, depending on the type of oven base you’d like to have, you might not even need to pour a pad.to be continued

Tuesday, May 11, 2010

from Bread Earth and Fire (The Earth Oven)

 searching for the perfect oven spot
Chapter 1

THE EARTH OVEN

Building the earth oven has been adapted from my book “Earth Oven Adventure.” It is the story about Abbott and Nancy Meader who built an oven in their backyard. Although they had some assistance from friends and me, Abbott and Nancy really did the bulk of the work. And there was a lot of work involved. If you can’t or don’t like moving heavy materials around, then you shouldn’t be building this type of oven. Of course you could always have someone build it for you or help you with it, but if you personally get involved in the physical part of the process, I believe you'll have a greater appreciation for your earth oven. You don’t have to be a mason or someone with special skills. All it takes is desire and not minding the mud you’ll have on your hands. You can use this section of Bread Earth and Fire as a template for constructing your own earth oven. All the information you’ll need will be right here for a 22 1/2 inch hearth diameter oven. I’ve chosen this size because I’ve already made some ovens with this hearth diameter, and they’ve worked out really well. If you want to change the dimensions, then your material quantities will change accordingly, but the basic principals remain the same. Consider reading Build Your Own Earth Oven by Kiko Denzer. He more than anyone else made this low-cost method of oven construction available to everyone.
to be continued