At Capacity: Is Your Exhaust Fan the Right Size?

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Most exhaust fans are not ‘one size fits all’. The capacity of the fan is vital to making sure that it operates correctly, and effectively ventilates the unwanted moisture from the room.

The size of the exhaust fan required depends on a variety of factors, such as the exhaust fan size of the room, available airflow and the wall/floor covering materials in the room. When installing an exhaust system in your home, Kenner Electrics calculates the volume of fresh air in the room and the number of air changes required. This allows us to provide a professional, customised solution that suits your homes unique needs.

Under-Sized Exhaust Fans

If an exhaust fan is not powerful enough for the space, it will not be able to effectively remove the undesirable humid air from the room. The resulting moisture build-up can create the perfect conditions for mould to grow, which has significant associated health risks.

Over-Sized Exhaust Fans

If an exhaust fan is too powerful for the space, it will cause drafts and make you feel cold (not great when you get out of a warm shower!). If the door is closed and there is not enough or has no proper air flow under the door, the fan may also wear out too quickly because it is trying to suck more air out of the room than is available. This will also cause it to be noisier than it should be. As larger capacity fans are usually more expensive to buy and cost more to run, you don’t want to waste money on getting one that is too big for your space.

Kenner Electrics installs exhaust fans
Kenner Electrics calculates the best sized exhaust fan for your space and designs a customised exhaust solution for your unique needs.

How to Measure What Size Exhaust Fan you need

In Australia, the capacity of exhaust fans is measured in m3 per hour. This is the maximum amount of air that the fan can move within 1 hour. Knowing the size of the room (length x width x height in meters) and the desired number of air-changes per hour allows us to choose the correct exhaust fan. The required number of complete air changes within a room per hour depends on the use of the room. For example, a separate toilet will typically require 6-15 air changes per hour, while a bathroom fan with shower will typically require 15-25 air changes per hour.

Universal Fans has a handy calculator to help you find out what sized fan will best suit your space.  

Choosing The Right Bathroom Exhaust Fan

Bathroom exhaust fans are a great way to reduce mould and moisture and help improve your indoor air quality.

Kenner Electrics designs and installs ventilation systems to help avoid mould and moisture issues. Whatever the problem, we provide customised solutions and design the best exhaust system for your home.

By calling us, we can suggest an approximate fan capacity based on your room size, room height and usage - it's that easy!

Why Choose Kenner Electrics?

Kenner Electrics is your trusted local electrician. We have a friendly and professional team of highly qualified, experienced and licensed electricians ready to handle all your commercial and residential electrical needs.

We provide up-front pricing with a clear explanation of the work required to avoid cost overruns. We provide prompt and efficient service and prioritise safety on each and every job. We are fully insured, licensed and accredited, we're a member of the National Electrical & Communications Association, and we are a registered electrical contractor with Energy Safe Victoria. We always provide compliance certificates for all completed electrical installation work.

We're one of the top rated electricians in Melbourne with over 250 genuine 5-star reviews from residential and business customers just like you.

Call our friendly team on (03) 9996 0663 or contact us online now.

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