Good ventilation is important for the whole house, but is vital in areas that create more moisture, such as kitchens and bathrooms. Without proper ventilation, bathrooms can be prone to condensation, damp and black mould. If not dealt with, persistent moisture in the bathroom could spread, leading to dampness in other areas of the house.

A mechanical extractor fan can be a good way to remove moist air from the bathroom, but it is important to choose the right one. A shower fan removes moisture from the air in a bathroom and rooms with a shower to help prevent the threat of damp. They are a one-box solution and typically contain all the elements you need for your convenience, rather than buying the items separately.

A bathroom extractor fan isn’t a luxury – it’s a must. As well as sucking away any unpleasant odours, it removes moisture from the air after a shower or bath, which can otherwise lead to long-term damage, especially if your bathroom doesn’t have an outside window. And if you plan on letting out your property, a bathroom extractor fan is a legal requirement.

Most domestic extractors pull through about 21 litres of air per second, which is plenty for an average-sized bathroom or shower room. To ensure the room gets fully ventilated, it’s a good idea to look for a model with an over-run timer, which keeps the fan running for a set period after you’ve turned it off.

The precise duration of the overrun is normally configured during installation, with most fans offering a range between 30 seconds and 30 minutes. You might as well tend towards the latter end of the scale, since the cost is very low: on average, a bathroom extractor fan like this uses around eight watts.

Most fans also come with a back-draught shutter to prevent cold air from blowing in from outside. The downside to these is that windy conditions can cause the shutter to clatter against the wall; if your outlet is exposed to the elements, it may be better to simply leave the shutter off.

Finally, if you think you (or anyone else in the house) will forget to turn the bathroom extractor fan on, consider a model with a humidity sensor. This automatically activates the fan when the level of moisture in the air exceeds a certain threshold. This sensor may need occasional cleaning, though, or the accumulation of dust or grime will hinder its effectiveness.

The most important things to consider when purchasing a bathroom extractor fan:

1. Learn about bathroom zones

Because electricity and water do not mix well, the UK has regulations restricting what types of electrical equipment – such as lighting, plug sockets, and extractor fans – can be installed in which areas of the bathroom.

The bathroom is divided into different zones. Zone 0 is inside the bath or shower, zone 1 is the area above the bath or shower (to a height of 2.25m). Zone 2 is the area continuing 0.6m horizontally away from the bath or shower. Anywhere beyond 'this, is classed as outside the zones'.

Devices have an IP Rating, which rates their resistance, or that of their enclosure, to penetration by solids and liquids. The first digit of the rating relates to solids and the second relates to liquids. Fans in Zones 0, 1, and 2 need high IP Ratings for liquids.

2. Consider when you want your fan to operate

There are several options when it comes to operating your fan. You can turn it on manually, using a cord switch, which is often the same cord as the light switch, or by remote control. Some fans have timers, turning them off a set time after the lights.

PIR (Passive Infrared Sensors) operate when someone enters the room, and fans with humidity sensors turn on and off when the humidity or moisture in the air hits, and then returns to, a certain level.

3. Think about noise levels

It may not be the first thing you think of, and you might not appreciate it unless able to see the unit running, but some extractor fans can be noisy. This can be an issue, especially if loud enough to disturb neighbours, if you have children and tend to bathe or shower after their bedtimes, or if you are susceptible to noise yourself. There are, however, many low-noise models available, and manufacturers provide a decibel level, to give an idea of how noisy they are even if you can’t see a demonstration of the model.

4. Research different designs

As with the noise issue, this might not be your first consideration – but your extractor fan is likely to stay in place for a long time, so you ideally need to appreciate its look and design.

5. Decide on your air exchange rate

The air extraction rate is measured in 'Litres per Second' (l/s) or 'Metres Cubed per Hour' (m³/hr). This is the rate at which the extractor fan removes air when operational and is one of the most vital factors. Building regulations say that a fan must extract no less than 15L/s in a standard domestic bathroom, so most models will cover this. Large or well-used bathrooms might need higher extraction rates.

6. Think about exterior grilles

As well as the fan, you will have a choice of fixed or gravity grilles, which are exterior grilles covering the vent through which the extracted air is expelled. Gravity grilles tend to have slats that are pushed open by the extraction process and then close under gravity. This prevents backdrafts when not in use but can be noisier, especially if they are located beneath a bedroom window. Fixed grilles can be quieter but might let in air through the slots.

7. Consider a heat recovery option

Heat recovery is usually an option for whole-house ventilation systems, where stale air is extracted from areas such as bathrooms, kitchens, and utility rooms, and passed through a heat exchange. At the same time, air is brought in from outside, filtered, and passed through the exchange, recycling much of the heat. Some innovative single-room heat recovery (SRHRV) systems, however, can do the same thing through a single unit.

When choosing a bathroom extractor fan, consider these options, so your house remains well-ventilated, helping avoid the damage of moisture accumulation.

What is The Best Bathroom Extractor Fan? Which is The Best Extractor Fan For Me?

How do you know which is the best extractor fan for you? There is no 'one size fits all' when it comes to fitting the right ventilation for your property. Unlike our competitors, we won't advise a product without knowing all of your requirements, such as the best location for the fan: wall, ceiling, or inline? Grill, roof vent or soffit?

You can contact our technical team over the phone to discuss your requirements.

We know that no two properties are the same, which is why it is important to ensure the right product is specified and installed correctly. This is why we offer a free home survey as standard to ensure the correct product is installed and you have the best extractor fan.

During a free home survey, your local expert will assess any condensation, damp and mould problems that you may be facing in your property and take readings of the relative humidity levels throughout the property.

All our ventilation specialists are highly trained in carrying out home surveys to identify any underlying problems and make recommendations to ensure the correct solution is provided, all complying with current Building Regulations.

Need help with condensation or mould problems?

Contact Us, and one of our local experts will contact you to learn more about your problems, offer free expert advice and make recommendations for a solution.

Top Tips For Choosing a Bathroom Extractor Fan

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