Pizza oven doors and chimneys: do you need them?

Why wood ovens need a chimney

A fire needs oxygen. In a wood or charcoal pizza oven, the chimney creates draught: hot gases rise up the flue and pull fresh air in through the oven's mouth or vents. That steady flow feeds the fire, keeps the flame rolling over the dome and carries smoke up and away.

Without a chimney, smoke spills out of the mouth, the fire starves of air and smoulders, and the oven struggles to get hot. Traditional brick ovens put the flue outside the cooking chamber at the front, so smoke leaves before it reaches the cook; portable ovens put it at the front or back depending on the design.

Do gas ovens need a chimney?

Most portable gas ovens do not have one. The burner is designed to burn cleanly, and combustion gases escape through the mouth. That is why gas ovens are more compact. They still must be used outdoors, never in an enclosed space.

Multi-fuel ovens like the Ooni Karu keep their chimney when you switch to gas, because the oven body is designed around it.

Doors: open or closed?

For pizza in a wood oven, the fire needs a lot of air, so you usually bake with the door off or with a door that has a launch slot. Ovens like the Karu have doors with adjustable vents or a glass window so you can see without opening.

Close the door to bring the oven up to temperature faster, to hold heat once the fire is out, or to cook slower dishes like roasts, bread and casseroles. If you close the door while a big fire is burning, it will starve of air and smoke.

Chimney dampers and vents

Some ovens have a damper in the chimney or an air vent in the door or under the fuel tray. Opening them increases draught and makes the fire burn hotter and cleaner. Closing them slows the fire and saves fuel, but too far and it will smoke.

As a rule, keep vents fully open while lighting and for pizza. Close them part way only when you want to hold a lower, steady heat. If the oven smokes heavily, open everything and check your wood is dry. Our how to light a wood-fired oven guide covers fire building.

Do you need a flue extension?

Flue extensions raise the chimney so smoke leaves higher up. They help when smoke drifts into a seating area, under a pergola or towards neighbours, and they can increase draught a little. Gozney, for example, sells a flue extension for the Dome.

An extension does not make a wood oven suitable for an enclosed space. It is about where the smoke goes outdoors. If smoke is a constant problem, the fuel is often the cause; see what wood to burn in a pizza oven and pizza oven not getting hot enough.

Note:Keep chimneys away from overhanging branches, fences and roof edges. Sparks can leave the flue. Check any local smoke control rules before burning wood.

Hoods and indoor use

Some people ask whether a pizza oven needs a hood, as in a restaurant kitchen. Commercial wood and gas ovens indoors need professional extraction designed to building regulations. Home portable ovens are outdoor appliances and are not designed for use under a kitchen hood.

For indoor cooking, choose an electric oven designed for kitchens; see can you use an outdoor pizza oven indoors and best electric pizza ovens for indoors.

Choosing an oven with the right features

If you want wood fire with easy control, look for an oven with a door that has a vent or window and a chimney damper. Our best wood-fired pizza ovens and best multi-fuel pizza ovens guides list what each model includes.

If you would rather avoid fire management altogether, a gas oven needs no chimney and no door; see best gas pizza ovens.

Frequently asked questions

Does a wood-fired pizza oven need a chimney? Yes. The chimney creates the draught that feeds the fire and carries smoke away.

Should the door be open or closed when cooking pizza? Open or off for pizza in a wood oven, so the flame gets air. Closed for heating up and slow cooking.

Why does my pizza oven smoke out of the front? Poor draught: wet wood, too much fuel at once or closed vents.

Do gas pizza ovens need ventilation? They must be used outdoors in open air, but most do not have a chimney.