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Can You Extend the Flue on a Pizza Oven?

Can You Extend the Flue on a Pizza Oven?

Do you own and operate a pizza oven? Are you wondering if it’s possible to extend the oven’s chimney flue? Then keep on reading and the Trade Price Flues team will tell you everything you need to know about extending the flue on a pizza oven…


Pizza ovens aren’t a brand-new invention, but they have certainly been growing in popularity in recent years - and showing no signs of slowing down either!

Many restaurants are now investing in a pizza oven, so they can offer delicious, authentic pizzas that can be cooked rapidly (and scoffed even quicker). They’re also a super popular option for festivals, wedding receptions, and other outdoor events as they look cool and provide a great option for modern catering.

If you are going to operate a pizza oven, understanding the dos and don’ts is crucial so that you can fire up the oven efficiently and continue to use it safely.

One of the most important things to understand is why you need a pizza oven chimney flue and what to do if you think you might need a pizza oven flue extension. Here, we answer those questions for you and introduce you to our range of high-quality pizza oven flue kits to help you find the right option.

Why do you need a pizza oven chimney flue?

Picture this: your pizza oven is all set up at a beautiful event venue; hungry guests are ready for a slice of the action. The next thing you know, there’s smoke coming from the oven, spoiling the atmosphere with uninvited fumes.

The reason why the pizza oven is producing this unwanted smoke is probably because it hasn’t been vented properly. The moral of the story: the need for sufficient ventilation is the main reason why pizza oven chimneys are so important.

Most people aren’t aware of just how essential it is to have a chimney in your pizza oven, but like any other solid fuel-burning appliance, it requires adequate air circulation and ventilation to function effectively and safely.

The main benefits of a pizza oven chimney:

  • > Ensures the flame can be lit and that the fire can continue to burn properly.
  • > Prevents smoke and fumes from escaping out of the oven into the space it is in.
  • > Helps remove smoke from inside the oven to improve the taste of the food being cooked.

What’s the science behind pizza oven chimney flues?

A pizza oven is similar to any other wood-burning stove, so the process is pretty much the same. As the flames inside burn, the hot air within the oven itself and the cold air on the outside cause an imbalance in pressure. This is what’s known as the ‘draw’ or the ‘draught’.

A chimney works to draw the hot air and smoke upwards, so it leaves through the flue, rather than getting trapped inside the appliance or being blown into the space the oven is in. The cold air is drawn into the oven from the front, ready to feed the fire and improve the performance of the appliance.

What type of flue for a pizza oven

The best type of chimney flue for a pizza oven

A pizza oven can only do its job effectively if the air inside the flue is warmer than the air outside. To make sure this is the case, you need to equip your pizza oven with the correct type of chimney and flue.

A twin wall flue is the best kind of flue for a pizza oven, as it retains heat extremely well.

A single skin stove-pipe is another possible option. However, we wouldn’t recommend this over a twin wall flue because they aren’t as well insulated and produce a lot more smoke as they take much longer to heat up. Plus, they can be pretty tricky to install, too.

Chimney flues and adequate venting become even more important when it comes to using pizza ovens indoors, which is where pizza oven flue extensions often come into the picture.

Note - when it comes to installing a twin wall flue for a pizza oven, it’s essential that you adhere to the correct distance to combustibles. This is the distance between the flue and the closest combustible material (e.g. a ceiling or wall). Here at Trade Price Flues, our twin wall flues require a distance to combustibles of 70 mm when installed in enclosed spaces and 50 mm when installed outside.

Can you extend the flue on a pizza oven?

The main reason people find themselves asking this question is if they’re looking to extend the chimney or if they want to build the pizza oven and its chimney into a structure.

The answer? Yes, you can extend the flue on a pizza oven. In fact, with high-quality products and some expert guidance, adapting the flue is fairly simple to do and offers a number of benefits.

Why get a pizza oven flue extension?

The main reason why somebody would install a pizza oven flue extension is so that the appliance can be used within a structure (be it indoors or outdoors). An extension kit will allow you to safely use a pizza oven in spaces such as an outdoor garden room, a gazebo, or similar.

As the name suggests, a flue extension extends the length of the chimney, allowing it to open above roofs and other internal structures.

Extending the flue allows for sufficient air circulation so that cool air can be drawn in to feed the flames while hot air and smoke are blown back outdoors. This improves the performance of the pizza oven, making for better-tasting food. 

Do you need a chimney on a pizza oven

How to install a pizza oven flue extension

Once you’ve decided which flue extension is best for your pizza oven chimney, you’ll need to follow these installation steps:

  1. Work out the flue size of your pizza oven model by measuring the internal diameter of the flue pipe.
  2. Determine the desired height of the flue extension. We offer three different flue sizes (500 mm, 800 mm, and 1000 mm), which can be connected or used alone. We always recommend a minimum of 500 mm protruding through the roof to accommodate the flashing, storm collar, and rain cap.
  3. Select your flashing - this provides a weatherproof seal.
  4. Optional step: select a roof support for extra stability.

Once you’ve done all that, you’ll then need to follow these fitting instructions (or the fitting instructions provided with your flue extension kit manual):

  1. Make a hole in the roof according to the diameter of the flue. For 100 mm, 125 mm & 130 mm flues, we recommend a 330 mm hole. For 140 mm and 150 mm flues, we recommend a 350 mm hole. This allows for a safe distance between the flue and combustibles.
  2. Make sure your oven is positioned correctly.
  3. Attach the roof support, if you’ve chosen to have one, underneath the roof, between the joists, ready for the twin wall to be placed in.
  4. Insert the adapter(s) into the existing flue.
  5. If the adapter isn’t secure inside the flue, use the fireproof rope or fire cement provided to create a solid seal.
  6. Fit length/lengths by slotting them together and securing them with the locking band. (At this point, you should have at least 500 mm of twin wall protruding up through your roof).
  7. Carefully cut a precise hole in the flashing with a sharp pair of scissors. For 100 mm, 125 mm and 130 mm flues, we recommend 190 mm flashing. For 140 mm and 150 mm flues, we recommend 210 mm flashing.
  8. Fit the storm collar above the flashing and secure with silicone where the collar meets the flue.
  9. Put the rain cap in place and secure it with a locking band.

Sounds a bit too complicated? You could always ask a professional to do it for you.

Either way, make sure to inform your home or business insurer if you wish to build your pizza oven into a structure. They will be able to tell you if this will be covered under your current insurance policy or if you need to upgrade your cover in some way.

You should also check with your local planning department to ensure you are not in breach of any Building Regulations or planning permission requirements.

Learn more about our pizza oven flue extension kits

Ready to improve the performance of your pizza oven with a flue extension and wondering what your options are? Sit back and relax while we take you through our selection of high-quality pizza oven flue extension kits designed for use with traditional pizza ovens.

All of our flue extension kits can be passed safely through roofs, gazebos, and other compatible structures as they feature twin wall components. They come in a range of dimensions, all created with the invaluable help of pizza oven manufacturers, architects, and customers.

Each kit includes the flue pipe extensions themselves as well as all the other must-have components, so you can get everything you need in one place. Nice and simple.

Please note, all of our kits require you to use the original single skin flue that should have been provided with your pizza oven. If you think you might want to replace this too, speak to one of our experts who will be more than happy to help, as this will likely affect the dimensions you’ll need.

125/130 mm Pizza Oven Flue Extension Kits

125/130 mm Pizza Oven Flue Extension Kits

Buy Now - 125/130 mm Pizza Oven Flue Extension Kits (Matt Black & Stainless Steel available)

140 mm Pizza Oven Flue Extension Kits

140mm Pizza Oven Flue Extension Kits

Buy Now - 140 mm Pizza Oven Flue Extension Kits (Matt Black & Stainless Steel available)

150 mm Pizza Oven Flue Extension Kits

150 mm Pizza Oven Flue Extension Kits

Buy Now - 150 mm Pizza Oven Flue Extension Kits (Matt Black & Stainless Steel available)

We make it easy to extend your pizza oven chimney flue

Now you’re all clued-up on how to extend the flue on your pizza oven, it’s time to start shopping for your extension kit.

We’re on hand with all the advice and products you could possibly need to vent your pizza oven in the safest and most cost-savvy way. All that’s left to do then is roll up your sleeves and perfect your pizza-making skills.

If you have any questions about selecting the correct extension kit for your pizza oven chimney, our experts will be happy to help. You can speak to them on 0161 6975 491 or at:

Shop pizza oven chimney flue extension kits now

Find more buying guides and advice on the Trade Price Flues blog

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