Do Pizza Ovens Need a Chimney? Ventilation F.A.Q.s
Pete McPherson Last updated 
If youâre reading blog posts about chimneys, youâre already in the deep end of pizza-making đ
(and can I come over for a pizza cookout??)
But building your own oven (or even purchasing a pre-built oven) brings A TON of options and questions.
Do pizza ovens need a chimney?
It depends on the type of pizza oven. All wood-burning pizza ovens (and other hard fuels) do need a chimney. Proper ventilation not only keeps smoke out of your face, but itâs also vital for air (and heat) circulation, which maintains temperatures and is a safety precaution. Gas pizza ovens should also have some sort of ventilation, but donât require chimneys (as no smoke is emitted).
I did a ton of research for buying my pizza oven, so allow me to dive into the details!
What does a chimney do?
Simply put, a chimney vents smoke and heat away from the cooking area.
With new heat being produced by the fuel (wood, etc), the smoke and hot air rise, but the chimney allows it to escape outside.
hot air has to escape!
Why is ventilation so important?
Although it might annoying to plan and think about when building pizza ovens, there are a number of important benefits:
1 - Chimneys keep harmful smoke/chemicals/debris away from you.
The last thing you want while cooking pizzas is a face full of smoke! Aside from being unpleasantâit could be bad for your health.
#duh
2 - A chimney maintains temperature and prevents flare-ups.
Burning wood is constantly creating NEW heat, and if you were to trap all heat inside an ovenâit could lead to flare-ups (dangerous), overheating and overcooking, or at best uneven cooking.
A chimney allows air to constantly circulate, which keeps the heat balanced and also allows you to regulate temperatures within your oven.
3 - Chimneys are a safety precaution.
Ovens can get HOT, and a chimney ensures that heat and smoke is kept away from walls/surroundings/your face.
Starting fires = bad!
Proper ventilation is really important for all pizza ovens, indoor and outdoor.
RELATED: Can you use a pizza oven in the rain?
What Types of Ovens Need a Chimney? Wood vs Gas
Not all pizza ovens need chimneys.
Wood and other âhard-fuelâ ovens
Anything that burns and produces smokeâlike woodâneeds a chimney to properly ventilate.
This usually includes wood pellets as well! Even wood/pellet Ooni ovens have chimneys.
Do gas pizza ovens need a chimney?
Since gas ovens donât produce smoke, they donât technically need a chimney.
However, ventilation is equally important in gas ovens! Air still needs to circulate and vent to avoid overcooking (or uneven cooking), and to prevent your pizza from tasting like gas (especially for propane pizza ovens).
Most gas pizza ovens are âopen,â meaning they donât have a door, and this is usually enough ventilation to maintain a good temperature.
Electric pizza ovens
Electric pizza ovens do not need chimneys, but like gas ovens, they still need proper ventilation.
Heat is still being generated, and needs a place to circulate and escape (just like all ovens).
What is an oven flue?
An oven flue is just a pipe that serves as the chimney! The words are often used interchangeably, but the flue is usually the duct and pipe connected to the oven that vents away heat, smoke, fumes, etc.
In indoor pizza ovens, the flue can be made of metal, clay, or bricks (or even a combination), and often goes through the wall or ceiling, up to the chimney.
Do I need a flue for my pizza oven?
If you have a wood-fired (or hard-fuel) oven, then yes! A chimney (or flue) provides heat circulation and smoke exhaust, and is vital for safety reasons, as well as proper cooking.
What position should I install ventilation?
If youâre building your own pizza oven, there are two main positions to put ventilation:
- The center
- The front (strongly preferred)
Generally, the heat source (burning wood) is positioned to the back or side of the pizza oven, and you donât want the flue (or chimney) directly above that.
Positioning the ventilation towards the front of the oven creates proper circulation of air/heat.
Also, even chimneys that appear to be coming up out of the center of the ovenâare often just being routed through the center at the top of the oven, with the actual flue opening being at the front.
Do doors work for pizza oven ventilation?
This depends on the type of oven.
Most gas ovens donât come with doors, and the open-front style allows you to achieve proper circulation without a chimney, etc.
Many wood-burning portable ovens (like the Ooni Karu, etc), have doors and chimneys. You should usually leave the door closed, as the chimney provides the proper exhaust and circulation.
Pizza Oven F.A.Q.s
Does a commercial pizza oven need to be vented?
All commercial pizza ovens need ventilation. The exact method will depend on what type of oven (wood, gas, electric, etc), but ventilation is necessary for proper cooking, heat circulation, and safety.
How big should the chimney be on a pizza oven?
The size of the chimney will depend on the type of pizza oven, and you should consult with the manufacturerâs guidelines! For wood-fired pizza ovens, the chimney should at least extend beyond the ceiling, patio cover, etc, and are usually 4 to 5 inches wide (10-12 cm). However, there are a lot more considerations that you need to consider with chimney size (depending on the size and position of your oven, the size of the opening, etc). Make sure to do proper research and consult with others!
Can a pizza oven chimney be at the back?
Usually, chimneys are at the front of the oven, because the heat source (burning wood, etc) is at the back of the oven. This is necessary for proper heat circulation and temperature control. For some non-wood burning ovens (like gas), it might be ok to place chimneys toward the back, but you should consult with the manufacturerâs guidelines.
Can you use OONI without a chimney?
For any Ooni that burns wood (or pellets), you do need to use the chimney! This is necessary for proper heat circulation and temperature control. It is also important for safety reasons. For gas ovens (like the Ooni Koda), no chimney is needed, as no smoke is emitted, and the oven opening should serve as the only source of ventilation.