My wife and I are starting over in our backyard I was recently looking into some cool things that I could do with all the brick from the current patio. The thought came to me: “I wonder if I could use regular bricks in a pizza oven?” So I did a little research.
So can you use old brick into a pizza oven? If the bricks are made of clay and are kiln fired (firebrick or red clay brick) they can be used for a pizza oven, but if they are concrete bricks you should stay away. Clay bricks can withstand the heat from a pizza oven, and concrete bricks can’t.
Brick type matters for many things in a pizza over, especially including how hot it will get and how long the oven will last over time. Firebrick is the preferred building material for most pizza oven builders, but a clay brick oven is better than no oven at all! Read on for more…
So What’s in a Brick and Which Do I Use?
Bricks are made of many materials and in many different manners, and then they’re put in many different places! The three most important types of brick that we’ll look at are:
- Firebrick
- Red Clay Brick
- Concrete Brick
Firebricks are specially made bricks that are built to handle high temperatures. They are often used in fire boxes, fireplaces, and industrial furnaces, as well as wood-fired ovens. These bricks are naturally white and made of a type of fired clay. The big difference with these bricks is that the composition of the clay (the alumina and silica) and the admixtures used allow it to be highly heat resistant, and less likely to crack or flake (aka spall). These can come in a variety of shapes, but are solid cored as they intended to really take the heat.
Red clay bricks are the more traditional red house brick. While they also come in many shapes, they are naturally red, have use a different type of clay (alumina and silica) and admixtures. These can be solid cored or hollow cored, but if they are hollow you’ll want to fill them with mortar before placing them. You might also see red clay bricks in the form of pavers for the road, driveway, or patio. These bricks are not as heat tolerant as firebrick and long use or high heat could cause them to crack or start to flake.
Concrete brick has a huge range of styles and can be found in a great deal of modern construction. Concrete is a very versatile house building material, and can be created with a huge variety of colors, shapes, and patterns. Sizes of concrete bricks can range from a standard brick to a cinder block. Concrete bricks are made mainly of portland cement, water, sand and gravel, and are poured and dried rather than kiln fired. Because the brick hasn’t been kiln fired and because of the materials it’s made from, it can not stand high temperature cooking.
Based on the composition of the bricks, the preferred order for using bricks in a wood-fired pizza oven is: 1. Firebrick, 2. Red Clay Brick, and Never. Concrete Brick. Firebrick is built for the high temperatures that your oven is going to produce. Red Clay Brick may be an acceptable substitute but won’t last as long in some locations and environments. Concrete brick should never be used, as they will deteriorate quickly and pose a real danger of explosion with the heat. You wouldn’t want to be eating concrete-topped pizza.
What Happens When You Cook in a Pizza Oven
A pizza oven is built from multiple layers:
- The base on the ground, which come in many shapes and sizes
- The walls from the base to the floor
- The floor or deck of the oven, on which will hold both the fire that is being lit and the food that is being cooked
- The dome which holds in the heat and acts as the ceiling
- The insulation covering the dome
- The door and chimney for the oven
The bricks that we’re primarily concerned about here are the bricks that make up both the floor/deck of the oven and the dome. This is where you’re going to see the highest heat from your fire, what’s going to have to hold on to that heat to complete the cooking, and what’s going to have to endure heat long after your fire has gone out. Fortunately, these bricks are usually protected from the weather by the insulation layer and the door, so they don’t have a lot of water or snow to have to deal with.
To cook in a wood fired oven you first build the fire on one side of the oven, and let it get up to temperature. At this point (which will reach up to 800/900 degrees Fahrenheit) you let the fire die, or keep it burning gently. The oven door gets closed and left for a few minutes to even out the heat. The heat has been absorbed by the brick that makes up the deck of the oven and the dome and will continue to stay hot for hours. Because the bricks get so hot and can cool so much (especially in a cold-weather climate), bricks that aren’t made of the right materials may not last as long as anyone would like.
It’s this heat that we need to be concerned about. The materials of the brick and the methods that they were created with are very important when it comes to both how much heat they can retain, and their durability when exposed to this heat repeatedly and for extended periods of time.
Choose the Right Brick for Your Wood-Fired Pizza Oven
It’s a fairly commonly held belief that firebrick is the best choice for a wood-fired oven. Firebrick is literally built for the application and will last a very long time if properly cared for. At the same time, red clay brick can be used to produce an excellent and safe oven, even if it won’t be as long lasting as the firebrick.
One major consideration while building a pizza oven is always cost. Firebrick can run from $2.50-$5 per brick in some locations, while red clay bricks can often be picked up for free from a building site that just wants to dump them or inexpensively from an online classifieds site – often about $.50 per brick.
So while it would be best to have a pizza oven made of firebrick, it’s a commonly heard saying that a pizza oven of red clay brick is better than no pizza oven at all! And a reminder – never use concrete bricks in the deck or dome of your pizza oven. It’s a huge risk that you really don’t want to take. If you don’t have or can’t find the right brick for a pizza oven, consider a tabletop gas pizza oven like the Ooni Koda 16 at Amazon.
Related Questions
Is recycled or reclaimed brick safe? As long as the brick is made of clay and is properly cleaned, many people have built fantastic ovens out of reclaimed brick. Make sure the brick is solid and not water damaged before installing
What kind of mortar should be used? A refractory cement should be used in building wood-fired pizza ovens. That kind of mortar is built for high heat and will last as long as your oven. There is some discussion out there about using 3 parts sand,1 part portland cement, and 1-part powdered fire clay (milled porcelain) instead, but YMMV.
How much does a pizza oven cost to build? This really depends on what’s going into the oven construction. Prices can vary from $300-$500 on the extremely cheap end, to over $5000 for a fully tricked out outdoor oven.
