Build a Small Scale Hearth Oven





Introduction: Build a Small Scale Hearth Oven

If you like baking crusty pizzas and breads then you need to bake on stone and you need to steam the oven for nice crusty breads. It can be kind of a hassle to use a regular oven what with shuffling the baking stone in and out between uses and pouring hot water into an even hotter preheated cast iron skillet to steam the oven. And during the summer wouldn't it be nice to bake your bread outside the house? So let's make our own dedicated small scale hearth oven!

Step 1: Materials

Materials list:

- toaster oven
- pizza stone
- about 12 inches of 1/4 inch copper tubing
- about 12 inches 3/8 plastic tubing
- steamer
- lid for steamer

I recommend choosing a toaster oven that is fairly tall so that your nice boules don't rise up and burn on top when they touch the upper heating element. Or to be on the safe side, you may just want to remove the upper element as I did.

Make sure to use an oven thermometer for the first several times so that you know how close the thermostat is. The thermostat on my old thrift store oven is off by about 75 degrees! ;(

Step 2: Aquire and Cut a Pizza Stone

I found a large round pizza stone at a thrift store and then cut it to fit in the toaster oven using a friend's wet saw.

Step 3: Add a Water Pipe

Cut a short length of 1/4 inch copper pipe. The length should reach from about an inch above the oven down to about an inch above the floor of the oven. My pipe came out about 9 inches long. Now drill a 1/4 inch hole through the top of your oven. (I pre-drilled my hole using a smaller bit first to make penetration with the big 1/4 inch bit a lot easier.) The pipe should fit nice and tight. If you need to caulk around the pipe make sure to use high heat caulk.

Step 4: Steam Mechanism

To create my steam I stopped by my favorite thrift store and picked up a Black & Decker Handy Steamer. It comes with a steaming basket which we aren't using for this project but you might want to keep it around in case you decide to steam some veggies to go with your fresh bread! :)

While you're at the thrift store look through the mismatched lids and find one that will fit fairly tight either inside or on top of the steamer base. I got lucky and found a stainless steel lid with a built in steam release valve. Upon removing the valve I discovered that the hole the valve fit into was exactly 3/8 inch and my vinyl tubing fit perfectly! :) A plastic lid would work fine too. If your lid doesn't come with a hole like mine you may need to drill a hole and buy the appropriate hose connector. You may also need to improvise a bit to get a good seal. I used some vinyl finishing trim I had on hand to get my lid to fit tightly.

Step 5: Fire It Up!

Okay, you should now be ready to put the pieces together and bake some bread! A good test for the oven is to see if you can make a crusty baguette. :) First preheat the oven. Once the oven and baking stone are fully preheated, start up the steamer and get it cranking at full force but don't connect the tube to the oven pipe yet. When all is in order use a peel to slide your risen dough directly onto the stone, then close the door and connect your steam tube. Oven spring mostly occurs during the first ten minutes so after that you can disconnect the steamer and continue baking.

NOTE: Keep an eye on your wattage to avoid tripping circuit breakers or blowing fuses. My toaster oven is rated at 1500 watts but I took out one element so it actually only draws about 750W. The steamer pulls 650W. So that makes a total of 1400 watts / 120 volts = 11.7 amps which means I can safely use a 15 amp circuit. If your particular setup keeps tripping a breaker you may have to run a heavy duty extension cord from a different circuit in your house to power one of the two appliances.

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    12 Discussions

    I would have never thought to pump water , even in the form of steam, into an electrical appliance!
    Not really an issue, just a visceral reaction.
    Very inspirational, could it be applied to a full size oven?
    I also love the idea of adding something to the outside of the oven for insulation.

    insulate it. it'll get hotter and you'll use less energy. silicon cock can withstand high temperatures stick some "stuff" on the outside and hold in that heat.
    Do you think electricity grows on trees?

    I like your use of Thrift store Items. keep it out of the landfill and make it work for a living.

    but I would caution you on your use of VINAL, especially with steam. VINAL is not food grade and leaches Hormone disruptors into water. Thats why waste lines are PVC and not supply lines. (note: exception, CPVC). The V in PVC: VINAL.

    Hope I've been Helpful and "Nice" (note: there is a "be nice" policy. if your not nice you will be tortured till you become so.)

    Very nice 'ible!! I'll definitely try this.
    What hearth temps can you reach?


    1 reply

    I haven't used it for a while but I think the temperatures got up to 450 or 500. The biggest problem was that it took a long time to preheat. I think this was largely caused by my removal of the upper heating element. Also the single pane loose fitting door leaked a lot of heat. I still bake often but I use my regular full size oven and just spritz the bread with water before putting it in the oven. Sometimes I've preheated a cast iron skillet in the bottom of the oven and then poured water into it as I put the bread in to bake, but that sudden billow of steam really makes me nervous... :(

    I love making bread and pizza ever scene I got my bread machine ($3 dollars at a yard sale with original recipe book). this could be a great addition to the dough setting.


    I wonder if you couldn't put, say, some dill or garlic in the water in your steamer like you would while steaming vegetables. Also, there's no law that says you MUST plug the oven in the same outlet as the steamer to keep your circuit breakers from tripping.

    This is really neat. I always wondered about the best way to introduce steam. Job well done!

    A pizza stone is just terra cotta or ceramic. You could just buy some tiles (unglazed). Might be cheaper, and can be fitted to size without using a saw.

    1 reply

    Actually, I've tried using the cheap unglazed tiles and have had them break. They especially seemed to break easily when I tried using them close to the heating element as is necessary in a toaster oven.

    So baking on a stone is the secret? I never knew that!

    Very interesting my friend!! I have always wanted to have an effected economical way to do this.. I believe you have just set me on the right path. Thank you. Great effort by the way!!