I chose a clay oven because it is more conducive to cooking pizza, yet allows me to bake bread in it, too. Clay heats up quicker than brick, so it will get up to temperature quicker (about 800-900 degrees F). And, because it cools down quicker, I don't have to wait as long to bake bread in it. Also, a clay oven is cheaper and faster to build, and you don't need any masonry skills. If I were cookin
g in it on a more frequent basis, I would have gone with brick because it retains its heat longer and I wouldn't have to fire it up as often. Necessary steps to building your oven:
1. Build a base for the oven to rest on.
2. Put an insulation layer, composed of 6 parts Vermiculite to 1 part portland cement, between the base and the slab that the oven sits on.
3. Pour a cement slab.
4. Spread a bed of clay/sand mortar mixed 1:1 using a 1/4" notched trowel and set the hearth bricks (hearth bricks must use firebricks).
5. Cover the hearth bricks with 2 sheets of newspaper. This will keep the hearth clean while you build your dirt form.
6. Set a row of firebricks on top of the hearth that denotes the perimeter of the inside of the oven. (see picture in album). This will protect the interior walls of the oven from being chipped and scraped by your oven tools in the future.
7. Build a dirt form. When removed, will be the interior of the oven.
8. Build the entry to the oven using firebricks, and install a chimney with a 6 inch diameter opening. (You do not have to incorporate a chimney.)
9. Connect the dirt form to the oven entry keeping in mind that the height of the entry must be as close as possible to 63% of the height of the dome, and the entry width is % of the dome height. For example, dome height = 15 inches, and entry height = 9.5 inches, entry width =
10. Cut a rubber membrane to shape and cover the dirt form.
11. Coat the rubber membrane will olive oil. (This will help the rubber membrane separate easily from the dome of the oven and keep the dome clean once the dirt form is removed.)
12. Mix a batch of sand and fireclay to a ratio of 2:1 and build a 4 inch layer of "mud" over the form. I use a 2:1 mixture for this layer because it results in a less sandy oven interior. This is your "oven layer."
13. Allow this to dry naturally for 1-2 weeks, if possible.
14. Mix a batch of sand and fireclay to a ratio of 4:1 and also mix in 1/2 part wood shavings (the kind you buy at a pet shop). Build a 4 inch layer of this "mud" over the "oven layer." This is your "insulation layer." The wood shavings, after repeated use of the oven, will eventually burn out and leave air pockets in the insulation layer.
15. If possible, allow this layer to dry naturally for 2-3 weeks before you proceed. It will result in less cracking oven the oven. If you want, however, you can proceed with building the "insulation layer."
16. Once dry, fill in any cracks that have developed with 4:1 "mud."
17. Dig the dirt form out, and remove the rubber membrane.
18. Sweep or vacuum up any dirt from the hearth and inside of the oven.
19. Burn a small fire to help the oven interior dry out. In order for the oven to get up to maximum temperature, the oven has to be bone dry. So it may take several fires inside the oven until that is accomplished.
20. Build a permanent roof over the oven to protect it from the weather. If you don't want to do this, you can cover it with a tarp, but you probably won't want to cook in it if rain is in the forecast.
21. Cook your favorite pizza and celebrate your accomplishment! Resources:
Books: Build Your Own Earth Oven, by Kiko Denzer; The Bread Builders: Hearth Loaves and Masonry Ovens, by Daniel Wing and Alan Scott
Firebricks: Star Building Materials, 2923 Symmes Road, Fairfield, OH, 45014. 513-942-7827. (At the time, they had the lowest price on firebricks.); Brick Tec, Inc., 6003 Meijer Drive, Milford, OH, 45150. 513-831-0012
Fireclay: Star Building Materials, 2923 Symmes Road, Fairfield, OH, 45014. 513-942-7827. (At the time, they had the lowest price on fireclay. Call first to make sure they have it, though. They were out of it at the time I built my oven); Western Hills Builider's Supply, 6801 Harrison Road, Cincinnati, OH, 45247. 513-574-6200. (They always had fireclay in stock when I needed it. But, beware, this place is off of the Rybolt Road exit on I-74.) Sand: If you have a pickup truck, Star Building Materials is the cheapest place I found to purchase sand. You get a tractor scoop for approximately $17 which is all the sand you need. Also, their sand was more angular, which helps it lock together when mixed with the fireclay, which results in a stronger oven. Vermiculite: Star Building Materials, 2923 Symmes Road, Fairfield, OH, 45014. 513-942-7827.
