A flue extension kit consists of stainless-steel chimney pipes and connectors that allow you to increase the height of your pizza oven’s exhaust flue. Extending the flue draws the smoke and gases away from the oven more efficiently for better combustion. It also increases the draught through the oven, so you get better air circulation for cooking the perfect crust.

Many pizza oven models come with a short section of flue that raises the chimney about 500mm above the oven dome. While this is fine in calm conditions, it can cause issues in windy weather or on uneven terrain, where smoke and heat can blow back down the flue. Adding a flue extension raises the chimney release point above your oven to prevent backdraughts. Extensions are also useful if you have covered your oven with an outdoor kitchen cabinet or pergola that restricts airflow through the short flue.

Choosing the right flue extension kit

When selecting a pizza oven flue extension kit, you first need to determine the internal diameter of the original flue of the pizza oven. Custom flue extensions are made to fit the dimensions and diameter of your oven’s flue outlet. You also need to consider:

• Single or double wall flue: Double wall flues provide insulation to retain heat and resist condensation and will also reduce the distance to combustibles, a must if you are planning on extending through a wooden garden structure.
• Diameter: Match the interior diameter of your oven’s flue.
• Length: Extension pipes commonly range from 250mm to 2m long. Calculate the needed length based on your oven height and ventilation needs.
• Material: Stainless steel is recommended for external use
• Accessories: Our Pizza oven kits included everything needed to complete the job 

Installing your pizza oven flue extension

Once you have the right flue extension kit, it’s time to install it properly:

1.Turn off your pizza oven and allow it to fully cool if it has been used recently. The flue can reach extremely hot temperatures.

2.Use a damp cloth to wipe away any dust or debris from the top of your oven and the flue outlet. This allows for a tight seal when connecting the extension.

3.We would recommend keeping the original length of the flue from your pizza oven as this usually has a built-in damper and extending from the top of this piece.

4.Assemble the extension kit according to the manufacturer’s instructions. Usually, this involves stacking extension pipe sections and locking the connectors between them. Place a rain cap on top and secure any accessories.

5.Have someone support the chimney extension as you attach the first section to the oven’s flue outlet. The extension pipe should sit flush and slide smoothly into place.

6.Continue adding extension sections, making sure that all the locks and connectors are properly sealed at each joint.

7.Once fully assembled, ensure the extension sits vertical and tight. Mark the height on your wall to monitor any shifting.

8.Check local regulations regarding required clearances from combustible materials around the chimney. Leave ample ventilation space around the flue.

Seasoning your flue extension

Before making pizza in your newly updated pizza oven, it’s important to properly season or cure your flue extension. This prevents any manufacturing oils or residues from affecting the oven flue. Follow these steps:

1.Build a small fire using kindling in the oven’s flue chamber

2.Keep the fire small and allow it to burn for 30–45 minutes. This helps burn away any residues inside the flue extension and prepares it for use.

3.Avoid cooking pizza during the first fire, just focus on burning cleanly through the extension.

Using and maintaining the flue extension

Once installed and seasoned, your flue extension kit will help optimise airflow and venting for peak oven performance:

• Monitor draught and airflow. A good fire should draw steadily up through the flue.
• Clean the extension regularly by scrubbing away soot or creosote deposits from the interior walls.
• Check for any leaks or damage, resealing joints if needed.
• Ensure the chimney remains clear of debris, plants, or animal nests that can block airflow.
• Be mindful of environmental conditions like wind and rain that can impact the flue draught.
• Avoid operating the oven in high winds that can blow smoke and embers down the flue.

Troubleshooting flue extension problems

If you experience issues with your oven after installing a flue extension, some common problems to look for are as follows:

• Backdraughting: This is when smoke blows back down the chimney due to wind or sufficient draught. Try a longer extension or relocating the oven.
• Poor heat retention: This can happen if the extension is too long and cools the gases too quickly. Use an insulated double-wall flue or shorter extension.
• Leaks: Small leaks where sections connect can reduce venting performance. Reseal joints with silicone sealant.
• Blockages: Build-up inside the flue or debris at the rain cap can block airflow and cause venting issues.
• Incorrect installation: If fitted poorly, the extension may be unstable or sit at an angle that prevents proper draught.

Getting the most from your flue extension

Adding a high-quality flue extension to your pizza oven provides huge benefits in terms of ventilation, temperature control, and enabling you to bake in all weather conditions. Take the time to correctly install and maintain the extension, and it will take your homemade pizzas up a notch!

Hopefully, this guide has given you all the key information you need for successfully installing and using a flue extension kit with your outdoor pizza oven. Having the chimney at the optimal height and airflow really unlocks the full potential of your oven. With the right flue kit in place, you can become a true pizza pro, making artisanal pizzas from the comfort of your own back garden. Enjoy!