This is a painting on the closed shutter of a pizza restaurant in Marsailles, France. Commerical pizza ovens are usually operated with a fire burning in the oven, and the door open, as in this painting. It hot work, especially in a Provençal summer, so the pizza baker in this painting is depicted working sleavless.

There is really no difference between a “bread oven” and a “pizza oven.” Because an oven used primarily for baking pizza must be operated with a fire burning within the oven a “pizza oven,” even when operating in a commercial environment, does not need to be especially massive. Thus, both at home, and in a restaurant, an oven that is primarily being used for pizza, as opposed to an oven that is being primarily used for baking multiple batches of bread, can be an oven with a comparatively thin refractory shell. Since a bread oven and a pizza oven are really the same thing, please read “Bread Oven Basics” before reading this page. I also discuss this issue in more detail, below.

Restaurants all over the world operate wood ovens for making pizzas. Many people dream of cooking pizza in a back-yard oven. Is the pizza always better because the oven is heated with wood? No. The secret to “the best” pizza is a hot oven, not the fuel source. While wood fired ovens potentially make incredibly fine pizza, simply heating an oven with wood does not guarantee success. The oven has to be really hot — pizza baking temperature is 750F (400C).

The wood fired oven is at approximately 750F (400C) after the oven is first fired with wood. Here is how it works. Remember that in traditional settings — homes, village ovens, bakeries — the main reason to fire up the oven was to bake bread, not make pizza. The traditional method for heating an oven to bake bread is to fill it with wood, get the oven walls so hot they glow white, and then, after about one and a half hours, to sweep out the embers, wait some time for the oven to cool from 750F (400C) to 450F (230C), and then load the oven with bread dough. For those of you who might use this description as a practical guide — these temperatures can be used as rough guides — as goals. The traditional moment to bake pizza and other hearth breads is just after the oven is swept clear of embers and before the oven cools from the initial post-firing 750F to 800F (400C to 425C) to a more realistic bread-baking temperature of 450F (230C). Pizza, and other hearth breads fit into traditional bread baking as treats. Whenever my mother made cookies I was allowed to lick the bowl and spoon clean. In a traditional oven firing pizza is like the dough snack.

Even when baking pizza at home for a party, the period of extreme heat will probably not last long enough to bake all the pizzas you need. The solution is to do what pizza restaurants do, rather than sweep out the embers, after the main oven firing push them to one side against the oven wall and then continue to add wood as needed to maintain the oven’s 750F (400C) temperature.

While it is easy to maintain the oven temperature in the vicinity of 750F (400C), you just have to keep burning wood, this can turn into a significant expense in a commercial setting. It is my view that most restaurants skimp on the wood — and thus operate their ovens well below the ideal temperature for pizza. When shopping for a commercial pizza oven, one question to ask is how much wood the oven consumes per hour to maintain a temperature in the range of 700F (370C). Ideally, this information will be offered in terms of weight, e.g. x pounds or kilos of aged hardwood per hour. While different hardwoods do have different weights, they are enough the same to provide you with a rough estimate of your operating costs.
Pizza should take no more than three minutes to bake. The European Union standard for Neapolitan pizza is a baking time of 60 to 90 seconds. Fast baking implies a thin crust and thin toppings. High heat creates flavors through caramelization of sugars that are difficult, if not impossible, to create when pizza is cooked more slowly. High heat also creates interesting textures — crisp crusts are guaranteed, as is some browning of the cheese and other toppings. High heat can lift pizza into another realm — into more than tomato and cheese heated up on top of some dough.

In planning a restaurant oven it is obviously important to consider the amount of food the oven can produce. Think of production in terms of recipe timing. If you can afford to keep a smaller oven hot enough to cook pizza in three minutes you may find that the smaller oven can actually produce more food — not to mention more distinctively tasking food — than a larger oven operating at a cooler temperature. An oven producing pizza in an average of 90 seconds, versus 5 minutes (300 seconds), produces pizza 3.3 times faster. To maintain this rate of cooking you may need to devote more of the oven floor to burning wood than you would in an oven operating at cooler temperatures, so the efficieny may not increase 3.3. times, rather, the gain may be something less, but it will still offer you significantly more production out of the same size oven — and significantly better taste.

Is there such a thing as a pizza oven? If there is, then what is the difference between a “pizza oven” and a “bread oven?”

One can bake pizzas in a bread oven, and bread in a pizza oven, so one aswer to the question is, no, there is no difference. On the other hand, an oven that is designed to maximize the quantity and quality of pizza production in a restaurant setting is different from an oven designed to maximize bread production in a bakery.

While there is more to a pizza oven than the oven’s interior dimensions, an oven designed for pizzas has a lower vault height than one designed for bread. Or at least it ought to. This is because one is trying to bake the pizzas at an extremely high temperature, and the lower the vault — within reason — the easier it is to accomplish this with a reasonable amount of wood use.

Pizza ovens are operated all day at high temperature, in contrast to bread ovens which may only be fired once a day, and only for a a couple hours. High heat stresses the oven. The oven floor, in particular, suffers significant stress from the constant burning. You will want to know how the oven your are looking at holds up to heat — how many years can you expect the dome to last at your usage level, and how many years the floor. All ovens should be designed to make repair reasonably easy — and this is especially important for pizza ovens that are located in busy restaurants.

Oven mass is not the key to the performance of a pizza oven, hence the many commerical pizza ovens that consist of comparatively thin oven shells — thin compared to those of bread ovens. This is not to say that mass is not helpful to a pizza oven, and that the ideal pizza oven may not be one with a comparatively low vault and substantive mass.
A classic bread oven, one designed for daily use by a commercial baker, or an oven designed for sharing by an entire village, is designed to be as massive as possible so the oven will retain as much heat as possible for as long as possible. For those of you new to the world of retained heat ovens, I will explain in a little more detail. Your kitchen oven is a metal box. The air is heated by gas or electricity. No heat to speak of is stored in the metal wall of the oven. Bread ovens work differently. Heat from a fire burning inside the oven is stored in the walls of the oven. Traditionally, once the baker feels enough heat is stored in the oven’s walls, the wood, now embers, is swept out of the oven, and the oven operates for hours, even for a day with no further addition of heat.

Aside from the possible difference of vault height, what differentiates most commercial “pizza ovens” from a “bread oven” is the mass of the walls. An oven designed for pizza will typically have a comparatively thin shell — under 3 inches (7.5 cm) — compared with a bread oven that might have a shell five to eight inches thick (12.5cm to 20 cm). A well-insulated “pizza” oven will, of course, bake bread. It will have enough heat stored in its wall to bake at least one batch of bread — but probably not two — and definitely not five batches all in a row without refiring.

If you want to be able to bake for twenty hours on a single firing of wood, then you require an oven that has more substantial mass, and that is well insulated. The ovens made by the master oven-builder Alan Scott are an example of this kind of oven.