Pizza Oven

How to build a Forno, wood fired brick oven

Al forno is a term that described cuisine in Italy which has the tradition of using wood-burning ovens and open-flame grills.  The brick oven has become a kind of symbol for "al forno" with its arched oven door and a wooden board upon which the food was put in and taken out.

One of the oldest evidence of a forno is in Pompeii, Italy.

Our forno in use during the annual All Hallows Eve Party.  Kirk is usually the baker but I was giving him a break.

My husband and I built our own forno in our back yard from scratch with a ton of help from my father-in law Ernie Ruffo, a retired stone mason, in 2009.  There are kits available where each piece is made out of unglazed ceramic that are then assembled at home.  A stand and an enclosure is still needed even when using a kit.

The base of our oven is 5'6" x 4'6" x 3' and is made out of concrete blocks, on a concrete foundation and is faced with river rock and clinker bricks.  There is an opening to store/age wood before burning.  We trim our fruit trees and use the clippings as kindling.  Only fruit, nut, or hard wood can be used in the oven - they get the hottest and do not have sap, etc.  This chart shows each species of wood and how it burns.  An oven could also be incorporated with an outdoor kitchen too. 

The completed oven

We chose to make our oven in the shape of a volcano as a reference to Mt. Vesuvius near Pompeii; where the oldest pizza oven was found. The bottom of the oven is 3' in diameter and is made out of fire brick and fire resistant mortar.

On top of the concrete block walls we placed a 2" deep steel pan that a friend of ours made to our specifications.  We wanted about a 6" overhang from the face of the brick and stone on the base.  Kirk created a template out of plywood for the 3' base and cut fire brick accordingly.  We decided that we also wanted fire brick on the floor of the opening to the oven.  This picture shows the void for the floor of the opening.

Next, we created the shape of the oven out of sand and covered it with a thin layer of stucco to form a shell that we could build to.

After the stucco was dry we started to dry stack the bricks.

Refractory mortar, or fire mud, needs to be used at all the joints at this layer.  We choose the light yellow for the floor of the oven. 

We used pieces of hardened mortar as spacers to create the angled walls.

All of the voids between the bricks need to be filled with fire resistant mortar, aka refractory mortar. After the voids are filled the entire exterior needs a coat of refractory mortar.  We also chose to apply mortar to the inside of the opening to the oven. 

At this point the bricks are supporting themselves so the sand and mortar shell can be removed.  Then a woven ceramic blanket is added to cover the entire exterior.  This blanket can insulate up to 2300 F which is key because the oven will get over 1000 F easily.

Then cover the blanket with a wire mesh.  This will hold the blanket in place and give a base for the stucco to adhere to.  For this layer of stucco, perlite needs to be included in the stucco mix as an insulator.  Perlite can be bought at your local hardware store.

Let the scratch coat cure before adding additional layers of stucco.  You do not want pockets of moisture that could expand and crack your oven when you fire up the oven.  The brown coat, or second coat, of stucco is where you can fine tune the shape of the oven.

Here you can see that we almost have the peak formed.  While Kirk finished the stucco on the outside, I filled any joints that were missing mortar.

Now let the entire oven cure for a few weeks depending on your climate.

We decided it was time to fire up the oven even though the exterior mosaic was not complete!  We were ready for some wood fired pizza.

The complete mosaic of dark grey smooth stones and lava rocks.

Things to remember

• Make sure that the opening of the oven is large enough for your pizza peel.  We buy ours from the local restaurant supply, but you can also purchase online.
• Use gloves that are rated over 500 F and that cover your forearms.  The oven gets really hot and you do not want to burn your hands or hair on your arms.
• Purchase a laser thermometer that goes to at least 1000 F.  The laser will help you find the best place to bake your pizza.

We referenced "Your Brick Oven" Building it & Baking in it by Russel Jeavons while we were building our oven.  A newer edition is available on Amazon

I will be sharing recipes and cooking methods with the forno in future posts.