Northwest Renovation Magazine

A Home Improvement Magazine

After traveling to Italy and enjoying a dinner cooked in a wood fired Pompeii oven, I had a dream to build my own oven. The dream went on the back burner until I visited Portland and enjoyed pizza at Ken’s Artisan Pizza; again I desired my own oven. Fast forward five years and a relocation to Portland. I finally decided I was in the right place to build my oven. Doing the research and consulting with my son’s employer, located in Seattle, who built his own oven, I figured it out and started the project. With only rudimentary masonry skills, I moved forward. Six weeks and $1,200 later, we were firing the oven and preparing for our first pizzas. Building a Pompeii oven is a very doable project that anyone with basic skills can complete. Fear not; just do it. Enjoy the foods you will create in your new oven.

STEP ONE

Pour a 66” concrete slab, 6” thick, reinforced with mesh. I thickened the slab around the edges by a couple of inches and added some rebar around the circumference to give the edges a little more strength, due to the fact most of the dispersed weight is around the edges. The inset photo shows the layout of the bricks for the base.

STEP TWO

Building the base was the most time consuming part of the process. I purchased 600 used bricks from Craigslist. The bricks are placed side to side (see previous photo inset) for strength. Most of the shear force from the weight of the dome is external, and by placing the bricks side to side you emulate having a double layer of bricks. At about 27” in height and to span the opening in the front of the base, which becomes a wood storage area, I used a piece of Mount Adams stone I purchased at a local rock yard. You could easily use a piece of metal angle iron to accomplish the same thing. After placing the lintel (header), do not add any more bricks to the sides of the wood storage area. Continue building the outer edges of the base to a height of 36”. There should be about nine inches from the bottom of the lintel piece to the top of your base. You will need to fill the back cavity, behind the wood storage area, with dirt and concrete scraps, to the level of the bottom of the lintel piece. The base is built to a height of 36” so that when an average height person is facing the oven, they are looking slightly down into it. This gives you a better view and more control of food you are cooking.

STEP THREE

Build a form to fill the space above the wood storage area; you should have a level surface on the entire interior of the base. Now put concrete mesh and rebar on top of the form and interior wood storage area wall. With all that in place, pour a 4.5” reinforced concrete slab. Let this cure for about a week before preceding the next step.

STEP FOUR

Using perlite purchased from a local nursery and Portland cement (not a premixed concrete), blend together five parts perlite to one part cement; I used two four-cubic-foot bags of perlite. Mix the ingredients dry and add just enough water to make the mixture come together. Fill from the slab to the top of the base. The insulated slab helps your oven retain heat that is lost through the floor. Be sure the finished surface is level with the wall bricks and very smooth. Let this cure for about a week before proceeding to the oven floor.

For the oven floor, use common firebricks available at any brickyard. Lay out the floor in the center of the base, making sure the firebricks are level and smooth; a little dry fire clay can be used to level the bricks, if necessary. Take your time to ensure you have a very smooth floor surface. This becomes your cooking surface.

STEP FIVE

Next you must encapsulate the floor in concrete, I used Masonite to wrap around the base walls and extend up to the height of the floor, 2.5”. I also cantilevered out about 6” in the front of the oven, to give myself a small work surface (see insert). The concrete is reinforce with rebar. Let this cure for about seven days before proceeding.

STEP SIX

Next you are going to build the dome. There are two schools of thought here. One is to mix your own high heat mortar or refractory cement, and the other is to purchase a premixed product. I decided on a premix product from Harbison-Walker Refractories Company, KS-4 Plus Castable refractory high heat cement. The product is extremely easy to work with and dries extremely hard. You will need approximately 330 lbs to complete the project. All of the firebricks are cut in half, a good day’s work. Your bricks will be 4.5” x 4.5” x 2.5”. Have a 5-gallon bucket available to soak your bricks; they must be wet or they will suck too much moisture from the mortar and it will not cure properly. The first step is to build the door arch, 20.25” wide by 12.75” high.

Once this is set and the mortar is dry, it’s time to build the dome, which is quite simple. Make a tool that is 21” long with a piece of angle iron attached to the end. Glue a washer down in the center of the floor; put the end of the tool in the washer and use the end with the angle iron to set each brick. The tool works as a third hand, holding each brick in place as you mortar it in. Because you are working off a pivot, in the end a perfect dome will be formed. As you reach the top, the angle is so steep you must abandon the tool and build a form for the last few inches of the top (see top right inset photo). Coat the entire exterior of the dome with refractory mortar.

STEP SEVEN

Next build the chimney, which sits in front of the door, outside the oven. Again, start with the arch 22.25” by 13.75” and custom fit the bricks to nestle against the dome. The top of the arch is a little tricky because you have to cut the brick in half, to create the opening that becomes the flue. Use your refractory cement for the chimney. You will need one 12” piece of flue liner for the top. Once the chimney is finished, it’s time to sit and wait another week, to let the bricks start to dry and the mortar to cure. If you live in a wet climate, a temporary tent shelter will help everything dry. After about a week you will need to start burning small fires in the oven to further dry the bricks and cure the oven. Start with a couple of sheets of newspaper and each day for a week, add more and more fuel until you reach the point of a roaring fire.

STEP EIGHT

The insulation is next: two boxes of Inswool-HP Blanket 8#. You want a total of 3” on the entire dome. Cover the insulation with screen mesh to prepare for stuccoing.

STEP NINE

Stucco the dome with two coats of base stucco and one coat of finishing stucco. Waterproof it, and you’re done.

Click on the link to view more step-by-step photos of the building of this pizza oven on YouTube.
http://www.youtube.com/watch?v=cI3FjoaTD7U

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