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How to Build a Brick Oven
Neapolitian vs Tuscan vs Barrel Vault
For thousands of years, brick ovens have been built on every continent by many different civilizations. As a result, there are a variety of oven designs to choose from. Choosing the design may be one of the most important decisions you make prior to building your oven.
Another popular Pompeii style oven is the Tuscan shaped oven. The Tuscan design has a more rounded dome, similar to an actual igloo. The oven opening is also larger than the Neapolitan oven. It does not reflect as much heat onto the oven floor but is said to hold more heat because of its higher curved shaped ceiling. This oven is more versatile. It can make great pizza and bread, but it can also be used for larger roasts and stews.
Pompeii style ovens are circular in shape and the most popular Italian brick oven design by far. There are two different popular variations of this circular, igloo shaped oven. The Neapolitan shaped oven has a very aggressive dome design. As a result, the oven ceiling is lower and can reflect more heat onto the oven floor. This oven can be used for roasting and baking, but its design is best for making pizza.
Barrel vault ovens have a half-barrel. cylindrical shape. The oven floor has a rectangular shape. These ovens are versatile, much like the Tuscan ovens. You can cook meat, vegetables, stews, bread, and pizza. The rectangular shaped floor allows for a larger cooking surface. For example, you can fit more loaves of bread on a 40 inch square cooking surface in comparison to a 40 inch round surface.
There are some disadvantages with this design. Because of its rectangular shape, these ovens do not distribute heat as evenly as a Pompeii oven. There will be some cooler spots inside the oven. These ovens also take longer to heat because there is more thermal mass (brick and mortar). Therefore, they require more firewood. However, because they have more thermal mass, a properly insulated barrel vault oven should retain heat longer that a typical Pompeii style oven.
I chose to go with the Tuscan style oven primarily because I’m using it to cook more than just pizza. The versatility of this design will allow me to cook entire meals, from baking bread to roasting lamb chops, and everything in between.
The oven floor measures 40 inches (inside diameter). There are several popular choices for insulating the floor (for more details watch part 3). I chose vermiculite concrete. I used about 10 cubic feet of vermiculite and one 94 pound bag of portland cement. Vermiculite can be difficult to find. A large garden center will often carry these in stock because they will often use vermiculite as an additive to the soil that they use for potting plants. The garden centers in the New York area usually sell them in large, 4 cubic ft bags. Garden centers will often carry perlite as well, and can be used in the same manner as vermiculite, and has similar insulative properties.
Insulating the Oven Floor
Oven Floor Installation
An oven that has been built properly will heat up more evenly than one that has a flawed design. Heat rises, and naturally, the top of the dome will give you the highest temperature readings. The oven dome will then reflect heat downward onto the oven floor. As a result, when you are cooking a pizza, bread, or even a steak dinner, heat is released from your oven floor, and heat is reflected from the dome, cooking food equally from the top and bottom. To ensure that your oven heats up properly, it is essential that you use a material for your oven floor that has the thermal properties to absorb, retain, and release heat.
I used firebrick for my floor. These are the same 2-inch thick bricks that I cut in half for the construction of the dome. I laid them down in a herringbone pattern. While this configuration may require a little more measuring and planning, it will allow your pizza peel to glide more easily over the brick and is less likely to catch an edge. Some mason suppliers carry other materials that can be used for oven floors. Some carry large square shaped firebrick (8 x 8 inches, 9 x 9 inches). These would be better because they are easier to install and there would be less seams.
Soapstone is another option. Soapstone has excellent thermal properties but is more expensive and almost impossible find where I live. I have seen people employ different strategies for floor installation. Some people use mortar to install the floor, and others don’t. I chose not to use mortar. My rational was that this oven will exceed temperatures of over 1000F. If there is no room for expansion, there is a greater risk that some bricks will crack. Prior to installing the floor, I used a clay/sand mixture to allow for the leveling of the bricks used for the oven floor (See Part 4). I was able to find the clay at a mason supply store near me. Any mason supply store that carries firebricks and other fireplace building supplies should carry bags of clay in powder form.
This article has not yet discussed the design of the base. Once you have decided on the size of your oven, you will need to decide on its orientation. Will it be a front-facing oven, or a corner installation? Front-facing ovens require larger bases. I chose a corner installation mainly because I wanted to save space. If you are planning on building an oven using my dimensions, I would recommend building a larger base. That will allow you more room for constructing the landing. In the part 6 video tutorial, I explain in greater detail, the problem I have with limited space and how I managed to work around those limitations to build my landing. There is one more important decision regarding the base that needs to be addressed in the planning stages. How high will your oven be? This is a personal preference, Unfortunately for me, I made my oven 3 inches higher that I had planned because, I was originally going to use 2 inches of ceramic fiber board to insulate the floor. When I decided to use vermiculite, I added an additional 3 inches to the height. If I ever build another oven, I would prefer the height of the oven floor to be at the same level as the lower part of my rib cage.
There are two schools of thought on how to start the construction of the dome. Should the dome be built on top of the oven floor, or should the oven floor be inside the dome? From the extensive research that I have done, an oven floor enclosed by the dome is said to perform better thermally. In other words, there is less heat loss. Some people have also argued that this method would allow you to remove and replace a broken brick. I have put some thought into this and still wonder if that is feasible. I decided to build the dome on top of the floor simply because it would be a little easier and less time consuming. If there is more heat loss using this method, it has not affected my oven’s perforce in any noticeable way.
If you are going to build your dome on top of the floor, as I did, you will have to decide if you are going to mortar the soldiers (first row) to the floor. A majority of people seem to frown on the practice of using mortar for the first row, because the oven floor will expand, and a permanent bond with the dome could cause cracking or worse. If you watch part 5, you will see that I did mortar the soldiers to the floor. However, I did so with a planned strategy. I felt that it would be easier to lay down the first row of my dome with each brick being leveled-off of the next, if I had a bed of mortar underneath each brick for adjustment.
I also saw a benefit in having a first row that would never move on me during the early stages of the construction of the dome. In theory, there would be a higher risk that expansion could cause damage to the dome. To prevent this from happening, I purposely did not soak the bricks used for the soldiers, or the brick on the floor. Firebricks absorb an incredible amount of water. Dry firebricks will quickly absorb the water in refractory mortar. As a result, the mortar forms a weaker bond to the oven floor. Any expansion of the floor would easily break the seal between the floor and the dome, allowing the floor to expand freely.
Dome Construction
Flue Vent and Chimney Construction
If a brick oven is vented properly, oxygen enters the oven entryway and feeds the fire, and all of the smoke rises up into the flue vent and exits the chimney. If the oven is located outdoors, certain weather conditions such as gusty winds, can disrupt this cycle from operating perfectly.
The flue vent is the opening in the arch which allows the smoke to enter the chimney. The size of this vent is dependent on two different variables. First: How large is the oven? A larger oven will burn larger fires resulting in more smoke. Second: How tall is the chimney? Chimneys create a vacuum effect. This vacuum draws smoke upward. As the oven heats up, so does the chimney. As the chimney heats up, the vacuum strengthens. In addition, taller chimneys will pull better that shorter ones. Simply stated: The taller a chimney is, the stronger the vacuum. As a result, smoke will be pulled up the chimney with greater force.
A more traditional approach to building the chimney would require using a clay liner and building the chimney up around it with either brick or stone. Aesthetically, this looks beautiful, and is a time-tested method that has been used for thousands of years. Another option that has become popular, is the use of a stainless-steel chimney pipe and capping. This option could save a great deal of time because they do not need to be covered with brick or stone.
As of writing this article I have yet to complete the chimney, but I will be using stainless-steel (next summer).
I used 3 layers of 1 inch ceramic fiber blanket to insulate the dome. Remember, a better insulated oven will heat up more quickly and retain heat longer. As a result, you require less wood when firing up your oven. You can also use vermiculite concrete or perlite to insulate the dome, but these materials are not as efficient as the ceramic fiber blanket. In order to attain adequate insulation with these alternatives, you would need to create a layer of insulation that is at least twice the thickness of the fiber blanket (6 inches minimum).
Note: Some countries have banned the use of ceramic fiber products for insulating brick ovens.
Dome Insulation
Rendering a brick oven, simply refers to the process of creating a permanent protective layer over your insulated oven. This is the final layer that shields the oven from all external elements such as rain, ice, snow and wind. I rendered my oven using regular concrete mortar (Type S). The same kind that you would use for laying bricks and cinderblock. The thickness of this layer should be around 1 inch thick. In addition, this concrete layer will provide a surface for your final decorative layer. There are many different aesthetic options for this final step. I used a stone tile and applied it much like how you would apply tile to a floor or a kitchen splash. When the tile was fully dry, I used a sanded grout to fill the spaces between the stones. Once everything was completely dry, I applied a stone and grout sealer, to prevent the absorption of water. Using this option yielded beautiful results but, is also one of the most expensive ways to finish a brick oven. A less expensive option is troweling a layer of stucco over the concrete rendering layer. Coloring agents can be added during the mixing process or you can apply several coats of paint after it has cured. A water sealer needs to be applied here as well.
Rendering
Floor Insulation
3 bags vermiculite (4 cubic feet each)
I bag Portland Cement 94 lbs (used entire bag to mix about 10 cubic feet)
Dome Construction
250 Firebricks
6 bags-50lbs Refractory Mortar
1 bag of mason's sand
1 bag of clay (power form)
Rendering
3 rolls 2ft x 25ft ceramic fiber blanket
1 roll chicken wire
3 bags type s concrete mortar (80 lbs)
1 bag thinset
approximately 40 sq feet stone tile (I bought extra, and returned leftover)
1 bag of sanded grout (25 lbs)
grout sealer
Optional
Stone veneer for chimney
Red reclaimed brick for decorative arches
granite for landing
additional type s mortar
additional materials for elongating the chimney, or stainless steel flue
Materials
If you would like to help support Artisan Made and future projects, you can make a donation here. Thank you for your support!