Bathroom ventilation systems are not only vital in removing excess humidity, but they help with the longevity of your bathroom decor as well as keeping nasty mould at bay.
Bathroom ventilation systems are not only vital in removing excess humidity, but they help with the longevity of your bathroom decor as well as keeping nasty mould at bay.

Things to consider

Bathrooms produce a lot of moisture, which means choosing the correct bathroom ventilation system for your space is essential.


All bathrooms require some source of ventilation, whether it’s an extractor fan or simply a window you can open. The UK regulations regarding just how much ventilation your bathroom requires are outlined in The Building Regulations Document F.

Size of bathroom and placement

Your bathroom will be split into different zones that are suitable for different electrical items. Typically, there is Zone 0, which is the area occupied by the bath and shower. No devices are allowed within this zone, apart from suitable equipment or insulated pull cords.
Zone 1 is the area above Zone 0. Only separated extra-low voltage (SELV) devices are allowed in this zone.
Zone 2 is the area above or either side of Zone 1. Only SELV devices are allowed in this zone.
If the size of the bathroom extends beyond Zone 2, a Zone 3 is created. Within this zone, portable equipment is allowed. However, they should be positioned so their flex length doesn’t enable them to be used in Zone 2.
Domestic extractor fans tend to come in two sizes: 4 inch/100mm and 6 inch/150mm. This size refers to the size of the impeller (the revolving part inside the extractor fan that sucks the air out).
To know what size bathroom exhaust fan you need, refer to the cubic metres per hour (m3/hr) measurement of your fan.
If your bathroom is 12m3 or less, you will need an extraction rate of at least 96m3/hr. It is generally a good idea to get a fan with a little more power than is required. Many fans offer a choice of two speeds and extraction rates, which means you can adjust it depending on how much steam is being created.

Types of bathroom venilation

When looking to install a bathroom ventilation system, it's helpful to understand the different types.


Perhaps the simplest solution to bathroom ventilation are bathroom windows. If you're renovating and thinking of installing a window, double or triple-glazed tilt and turn opens are usually the best because they swing outwards to maximise the amount of air that can enter the space.
The further away the bathroom is positioned from an external wall, the longer the 'duct run' will have to be. Our range PVC flexible ducting is available in 3m and 6m sizes.

Axial fans

Bathrooms that are situated within 1.5m of an external wall will typically have an axial extractor fan installed. These are not as powerful as the air must travel a shorter distance. However, they are often quieter because of this. Our concealed fan is a discreet axial fan solution thanks to its slim compact design.

Centrifugal fans

If your bathroom is situated over 1.5m away from an external wall, a centrifugal fan is the best choice. This is because they are mechanically designed to be more powerful and shift air over longer distances, which can make them a little noisier. In many cases, centrifugal fans are fitted into the ceiling.

Inline fans

An inline extractor fan can move the air over even longer distances of up to 40m for bathrooms that are further away from an external wall. Our sleek HiB inline fan is available in chrome and white, as well as a cool or warm LED illumination.

Benefits of a bathroom extractor fan

A bathroom extractor fan is the easiest way to ensure your bathroom meets the requirements set out in The Building Regulations. However, extractor fans have myriad benefits.
Reduce condensation: An extractor fan helps minimise the amount of steam that can engulf a shower.
Prevent mould: Added condensation can exacerbate mould. Over time this mould can grow and become harder to remove.
Extend the life of your bathroom: Bathrooms are a big investment. Condensation and mould can wreak havoc with the integrity of their structures, damaging fixtures and fittings beyond repair.
Keeps odours at bay: Damp, stale air can lead to unpleasant – and even dangerous – smells in your bathroom. The right bathroom ventilation fan can help solve this.

Get your bathroom ventilation system

Take a look at our range of bathroom ventilation fans to find the right system for you. Download our brochure for full specs or speak to one of our in-house experts in your nearest showroom.