Choose the correct duct size for your fan

When choosing a fan, the size of your existing hole or ventilation duct is crucial for both function and efficiency. On this page, we'll help you find the right solution – whether you have a hole that is Ø100, smaller than Ø100 mm, or larger than Ø100.

Do you have a hole smaller than 100 mm?

If your duct or hole is less than 100 mm in diameter, there are still good solutions available. At DUKA, we offer fans with a flat back, which can be easily mounted directly over the hole. These function as a flexible and universal solution where you do not need to adapt the installation.

However, it is important to be aware that a smaller duct will naturally restrict airflow. This means that the fan's performance will not be as high as with a larger duct diameter.

Do you have a Ø100 mm hole?

A 100 mm diameter duct is the standard for many ventilation solutions. Here you have the largest selection of fans, and you typically achieve a good balance between features, air exchange, noise level, and energy efficiency.

Do you have a hole larger than 100 mm in diameter?

If your hole is larger than Ø100 mm, it's rarely necessary to choose a larger fan. In the vast majority of cases, a Ø100 fan will be sufficient for the need.

Vi anbefaler i stedet, at du anvender en cover plate, which makes it possible to mount a Ø100 fan in a larger opening. It is both an economical and practical solution, giving you flexibility without compromising functionality.

Find the right fan solution

Whatever your duct size, you can find a solution that suits your needs. Use our fan selector to quickly and easily find the right model for your installation.