How to choose a chimney?


If you don’t know anything about chimneys, choosing the right one seems difficult. After all, a chimney is a long-term investment and a significant expense. If you choose the wrong chimney, you will either have to buy a second one or change the heating. Contrary to appearances, choosing a chimney is not complicated – all you need is a little knowledge. Read the article below and if you still have any doubts, please contact us and we will be happy to help.


Really! Check the diameter of the flue gas outlet of your selected stove and this will be the diameter of the chimney you need. Simple, right?

Next, determine what you will burn in the furnace and what exhaust gas temperature is provided by the manufacturer of your furnace.
Heating with coal and wood requires, in the case of ceramic chimneys, these chimneys must have a Zulassung of min. 600 degrees, and if you prefer a steel chimney, it must be a double-walled, heat-resistant chimney.

Pellet or oil heating generates lower exhaust gas temperatures. This means that the chimney may be allowed to reach a lower temperature. However, acids are produced in the chimney and deposited on the chimney walls.
In this case, you need a ceramic chimney with Zulassung for wet operation, or an acid-resistant steel chimney.
Gas heating generates such low combustion temperatures that you have even more options: a ceramic chimney, an acid-resistant steel chimney, or even a plastic pipe (in this case, consult the chimney sweeper to see if he will make any difficulties).

We recommend the universal ceramic chimney, which has Zulassung for all types of Brennstoffe. This makes it possible to easily change the furnace in the future. And with EU regulations constantly changing and emissions regulations constantly changing, it’s worth being able to change easily.

Take a look at what ceramic chimneys are available in our store.


Then check if your heating requires external air intake. If air is required (it is room-air-dependent), then you have several solutions:
you can supply air through a regular plastic pipe through the wall
use a LAS chimney with air inlet between the stones and pipes
use a massive universal chimney with a ventilation duct to supply air to the stove.
If you do not need an external air intake, a square ceramic chimney or a double-walled steel chimney (heat-resistant or acid-resistant – depending on the fuel) will suffice.

Your chimney should protrude at least 0.5 m above the top of the roof. If, for this reason, the chimney stands free for more than 1.5 m, ropes to strengthen the chimney and Einsenstabe are necessary to strengthen the structure at the corners of the chimney stones.
Adjacent buildings are also important so as not to blow smoke into your neighbors’ windows.

Stoves have very different flue diameters and sometimes it is more difficult to choose a chimney with the appropriate diameter.
There is no problem with steel chimneys, because they are available in various sizes, e.g. 150mm, 130mm or 120mm.
However, if you have decided to choose a massive chimney, the solutions are limited.
Standard ceramic chimneys are made in diameters of 140mm, 160mm, 180mm and 200mm (less often larger). If you are looking for a 150mm, 130mm or 120mm chimney, you must use a reduction, or rather an extension, because the chimney should always have a diameter equal to or slightly larger than the flue on the stove.
A convenient solution are ready-made sets with reduction, e.g.:
– Schornsteinbausatz 150mm
– Schornsteinbausatz 130mm
– Schornsteinbausatz 120mm

Well, then we can estimate what chimney diameter to choose. Of course, it would be better if you found out which stoves you are interested in and selected according to the above tips.
If you don’t have this opportunity, we will try to advise you.

For gas furnaces, we choose small diameters – a ceramic chimney of 140 mm, an acid-resistant steel chimney of 100 mm or 120 mm (of course, it may turn out that the diameter of the exhaust outlet will be even smaller, but it is better to have a diameter that is too large than too small).
Most new gas stoves require an external air intake, so the safest solution will be a 140 mm ceramic chimney with a ventilation duct.

It is difficult to choose the chimney diameter for oil furnaces, because there are very different furnaces with different flues on the market: from 130mm-250mm in diameter. It all depends on the model and power of the oil stove. If you have your eye on something, please check the diameter of the exhaust gas outlet from the stove. Or compare the cliques that interest you and see what order of magnitude they are. Remember, it is better to have a diameter that is too large than too small.
However, I think that a chimney diameter of 160 mm will be optimal, because most oil furnaces have small diameters of the exhaust gas outlet to the chimney. If you are planning a high-power boiler, you can try a D. 180mm chimney
What is important is that the oil heating chimney operates at lower exhaust gas temperatures, “wet”, where acids are already deposited on the walls of the chimney pipe. Therefore, you should choose a ceramic chimney for wet operation or an acid-resistant steel chimney.
Most often, oil heating does not require outside air intake, so you can use a room-air-dependent chimney, e.g. a massive universal ceramic chimney 160mm, stone 36x36cm. If you are interested in a chimney with an intake, I recommend a 160mm chimney with a Zuluft canal.

And again, pellet stoves work “wet”, so you need an acid-resistant steel or ceramic chimney with Zulassung for wet operation (or a universal ceramic chimney). For pellet heating, I recommend D. 160mm chimneys or, for high-power stoves, D. 180mm chimneys. Both room-air-dependent and room-air-independent ovens are available. So if you don’t know which one to connect to the chimney, I recommend a universal chimney with air inlet, e.g. a D. 160mm chimney with a Zuluft canal.

For a coal or wood stove, you need a ceramic chimney with approval up to T600 (higher smoke temperature) or a double-walled, heat-resistant steel chimney. The most common diameter is 160mm and we recommend it. More and more stoves require an air intake from the outside, so we recommend a universal chimney with air intake, e.g. a D. 160 mm chimney with a Zuluft duct.

Wood-burning fireplaces require chimneys with a diameter of 180 mm. Just like for stoves, you also need a ceramic chimney with T600 approval (higher smoke temperature) or a double-walled, heat-resistant steel chimney. We also recommend a chimney with air inlet, e.g. a D. 180mm chimney with a Zuluft canal.

Here everything depends on the power of the stove. If you are planning a stove with lower power, then D. 180mm will be a good solution. A large stove requires a chimney diameter of 200mm. Of course, you can choose from a heat-resistant steel chimney or a ceramic chimney for dry operation (Zulassung T600).
Depending on the type of stove model you are planning (room-air-dependent and room-air-independent), choose a chimney.
If you are not sure, we recommend a D. 180mm chimney with Zuluft duct or a D. 200mm chimney with Zuluft canal.

It is best to plan the entire heating system and select a chimney for it. The selection is easy, and if you have any doubts, write to us and we will be happy to advise you.