Extractor Fans Buying Guide

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Extractor Fans Buying Guide

Once you've finished a hard day's work, you can rest and enjoy a relaxing bath. There's nothing more annoying than being disturbed by the noise from the fan in your bathroom. This is where an extractor fan comes in.

Extractor Fans are essential in removing moisture and odours from your kitchen, bathroom, home or office. They work by transferring the air from the room to the outside atmosphere, by the venting system attached. For example, in a bathroom the airflow vents are placed at the top of the room, so the heat which rises will be transferred outside.

What is an Extractor Fan?

Extractor Fans are usually mounted to the wall or ceiling, and connected to a venting system which draws air from inside the room, and transfers that air outside. They are most often found in bathrooms and kitchens. Extractor fans prevent excess build up of moisture in your home. They will remove the water vapour out of the bathroom, once you've finished having a shower.

Types of Extractor Fan:

Axial: An axial extractor fan pulls the extracted air through an impeller, and then out through the hole in the external wall. They are the most common extractor fan, and ideal for bathrooms and smaller rooms where ducting of 2-3 metres is required

Centrifugal: Centrifugal extractor fans extract air at right angles to the fan intake, and then spins the air outwards to the outlet by centrifugal force. They can extract more air, and are suitable for rooms with longer ducts.

Inline: Inline extractor fans often sit in ceilings above the room, make a lot less noise and can be used in situations where extremely long ducting is required. They are ideal for rooms without an external wall, or where the noise of your extractor fan is an issue. They can be used to prevent heat loss, as there isn't a need for a hole in an external wall.

Where should I put my extractor fan?

To decide where you should put your extractor fan, consider which places in your home cause the most damp problems. In the bathroom, hot showers each day will generate a lot of water, heat and moisture. A temporary solution would be to open your window, but you wouldn't want to do this in Winter. It would be most ideal to place your extractor fan on the wall to the side of the shower. This is Zone 1 of the bathroom. An Explanation of Bathroom Zones is below.

Bathroom Zones

Zone 0 is inside the bath or shower itself. Any fitting used in Zone 0 must be low voltage and be IP67 rated.

Zone 1 is the area above the bath or shower to a height of 2.25 metres from the floor. In this zone, a minimum rating of IP45 is required but IP65 is also accepted.

Zone 2 is the area 0.6 metres away from Zone 1, and to a height of 2.25 metres from the floor. In this zone an IP rating of at least IP44 is required

Diagaram of a batfhroom with a bath and separate shower unit showing the different bathroom zones

Fan Size Considerations

There are many different fan sizes available to choose from. If you're retrofitting a new extractor fan into an existing hole, the fan size will be the same size. However, if you are designing and renovating a space, here's a handy guide on how room sizes match up to the hole size required:

Firstly, you need to measure the size of your bathroom. Use a tape measure to measure the height, width and length of your bathroom in metres. For example, let's say your bathroom is 4 metres long, 2 metres wide and 3 metres high. The volume would be equal to 4 x 2 x 3 = 24 m3. In a bathroom, it is recommended to have 4 air changes an hour as a minimum.

Therefore, the extraction rate of your fan is equal to:

Extraction rate = 24 x 4 = 96 m3/h

From here, you will be able to match the extraction rate to the size of the fan you need.


    1. 4 Inch Fans: Perfect for smaller rooms around the house, such as en-suite bathrooms and shower rooms. Rooms under 9 m2 are the ideal size for smaller fans
    2. 6 Inch Fans: Ideal for medium size rooms of over 9 m2 with higher moisture extraction needs. You may consider a 6 Inch Fan if you live in a home with your family or friends. Multiple people sharing one bathroom is frequent use will require a fan with a higher extraction rate.
    3. 9 Inch Fans: Ideal for larger rooms with many people. Suitable for offices, and commercial premises.
    4. 12 Inch Fans: Ideal for larger rooms, with high demand from customers in one space. Suitable for commercial premises, such as restaurants, offices, bars, cafés and gyms.

How to Choose the Right Extractor Fan for you

Hole Size Consideration:

The size of the hole in the wall is normally out of your hands when you are replacing an existing fan. It is important to ensure your desired fan is compatible to avoid extra installation costs and stress.

How to Turn the Fan On:

You have multiple options to turn a fan on. A fan can be switched on manually by a pullcord. A fan can also be switched on by a PIR sensor, which detects movement every time you walk into the room. A third option is a humidistat sensor, which switches on after reading the humidity level has risen above the limit or detects odour, and will switch off once the humidity is normal again and the odour is gone.

Noise Levels:

If you wish to buy a quiet extractor fan, please check the noise level to ensure this won't be an issue for your property. Typically, axial extractor fans have noise levels ranging from 35 - 45 dB, while centrifugal extractor fans have noise levels between 40 - 55 dB. Our collection of extractor fans have noise levels between 14 - 50 dB. All extractor fans are measured with a standard test of Decibels recorded at a distance of 3 metres away. This is an important factor to keep in mind when checking specifications.

Is a Heat Recovery option required?

Heat Recovery is usually a option for whole-house ventilation systems, where moisture is extracted from the bathroom, kitchen and utility rooms, and passed through a heat exchange. Fresh air is brought in from the outside environment, passes through the heat exchange, and recycles most of the heat. This allows for greater climate control.

Shower Extractor Fans and Fan Light Kits

Shower Fan light kits are packs which contain all you will need to install an extractor fan in the ceiling above your shower. The kits include the shower light, inline fan, outdoor grille, flexible ducting, the clips and connectors you'll need. Usually, the shower is the main source of excess moisture in your bathroom. The Fan light kit will help reduce the excess moisture. Our range of kits includes premium features, such as variable overrun timers giving you complete control.

Frequently Asked Questions

Q. What type of extractor fan do I need for my bathroom?

A. The best option would be an axial extractor fan, as you can mount it to the wall or ceiling. This allows for the ducting to go straight to the outside through an external wall.

Q. Do I need a bathroom extractor fan?

A. Yes, extractor fans will remove bathroom odours and minimise the mould and damp occurring from the humid air.

Q. Do I need an electrician to fit a bathroom extractor fan?

A. You will need a qualified electrician to install an extractor fan in your bathroom.

Q. What is the difference between bathroom and kitchen extractor fans?

A. Building regulations require bathroom fans to have an extraction rate of at least 54 m3/h, whereas kitchen fans must have an extraction rate of at least 216 m3/h.

Q. How do I know which Extractor fan I need for each room?

A. Bathrooms will require a 4 Inch Fan, and Kitchens a 6 Inch Fan.

Q. What size kitchen fan do I need?

A. Kitchens require a 6 Inch / 150 mm fan in order to meet Building Regulations.

Q. Do kitchen extractor fans need to vent outside?

A. Yes, as a kitchen extractor fan will remove the air from the room.

Q. Where do you put an extractor fan in a kitchen?

A. You place the fan close to the Cooker as this will generate the most steam, and not draw it across the kitchen.

Q. Are inline fans better?

A. Yes, as they are fitted outside of the bathroom, and are quieter with a more powerful motor.