Do I Need an Extractor Fan in My Bathroom

Do I Need an Extractor Fan in My Bathroom

Do I Need an Extractor Fan in My Bathroom

An extractor fan is a common installation in homes, offices and public buildings alike. But are they actually necessary? Or are they just a recommended appliance?

In this blog, we will provide answers to the question ‘Do I need an extractor fan in my bathroom?’

With new buildings being made to be as energy efficient as possible, and the UK aiming for 95% of its electricity usage to be low carbon by 2030, it is imperative to understand how we can make the most of our ventilation. This is where applications such as extractor fans and heat recovery ventilation units come in.

To prevent mould, fresh air should constantly be introduced into your dwelling daily, as it helps to regulate temperature and reduce condensation. Introducing fresh air can be as simple as having a ventilation routine, or installing extractors or MVHR units. Almost all of this is facilitated by ducting.

What is the process of a bathroom extractor fan?

The function of a bathroom extractor fan is to remove moisture and odours from the bathroom it is placed in. But how does it work? Below, we will highlight the process that this mechanical ventilation undergoes.

  1. The fan is powered by electricity. It is usually turned on through a dedicated switch, a light switch, or a timer connected to a shower. Once on, an electric current flows through the motor.
  2. Powered by the electric current, it energises the motor within the fan. This causes the fan to spoon, creating a low pressure zone within the fan housing.
  3. As a result of the low pressure zone, air from the bathroom gets pulled towards the fan, this includes air containing moisture or odour particles.
  4. The extracted air continues its way through the ducting of the bathroom extractor fan. Bathroom extractor fans are often associated with rigid ducting, although it is possible for flexible ducting to be used (although not recommended). It is worth noting that the efficiency of the extraction is supplemented by the straightness of the duct. The fewer turns, the better.
  5. The extracted air makes it to the end of the ducting, ending up outside through an exterior wall vent. On a cold day, you can see this leaving the vent as a collection of steam.

Do I need an extractor fan in my bathroom?

Do I need an extractor fan in my bathroom?

Legally, according to Part F of the UK building regulations. You must have mechanical ventilation in your bathroom (an extractor fan) if your bathroom has a bath, shower, or both. Especially if it is a new build.

If your bathroom only has a toilet, a window that can be opened is legally required, but mechanical ventilation is not. That being said, we would recommend mechanical ventilation in the form of an extractor fan regardless. But how would an extractor fan benefit a bathroom that only has a toilet in it?

A bathroom that has a toilet in it may likely be a smaller room with little ventilation. So an open window can be helpful to some degree regarding temperature regulation. But it’s no secret that toilets can end up being smelly. Having an extractor fan can increase the speed that smells are removed from a bathroom.

In regard to a regular bathroom with a bath/shower inside that legally requires mechanical ventilation, an extractor fan is the most logical and practical answer. A bathroom extractor fan works to remove the humidity out of the bathroom, which is especially handy if you have hot showers regularly.

You can make this process quicker if you choose to open the window at the same time that you use the extractor fan. By having it open whilst you shower, you are immediately removing a majority of the steam that will accumulate by using the shower. This means your extractor fan will not need to run as long once you have finished.

Do I have to use my extractor fan in my bathroom?

Although the law stipulates that you need mechanical ventilation in certain kinds of bathrooms, do you have to use the extractor fan? Legally, no. You do not have to activate your extractor fan, however, it would be wise to do so.

By neglecting to turn on your extractor fan or any similar kind of mechanical ventilation, you are allowing the chance for condensation to occur in the bathroom, if left unattended, this can quickly become mould.

Once mould takes hold of a surface, it has the potential to spread quickly, and go deep into surfaces. Mould generates an unsightly dark growth over the surface, which is complemented by a putrid smell.

Aside from the attack on your senses, mould also has the potential to aggravate or even induce certain health issues, depending on your level of sensitivity against the mould. This can be especially dangerous for children, as mould exposure has been known to lead to the death of children and adults alike.

Can a window ventilate my bathroom by itself?

An open window has the potential to ventilate a bathroom by itself. However, having an open window presents a few problems that are negated if you use an extractor fan. They are…

  • An open window can significantly affect the temperature of the room and its surroundings, this is only made worse during colder seasons and most evenings. An extractor fan is covered by vents, negating temperature loss. This can be improved if you invest in a MVHR unit.
  • A wide open window leaves the chance for bugs and insects to enter your home, and if you have pets, some may unintentionally end up exploring beyond the window!
  • Open windows, in some instances, can provide an opportunity for thieves.
  • With an open window, you don’t know when the humidity in the room has been reduced to an acceptable level. Most modern bathroom extractor fans have temperature sensors built in, this allows them to stop when the humidity level has reached a certain threshold.

Is MVHR better than an extractor fan?

In terms of outcome, a MVHR unit is better than an extractor fan. The thing is, a MVHR unit works almost identically, to an extractor fan, but with two key differences. MVHR units work to retain heat whilst delivering fresh outdoor air.  

This means that if you have a MVHR unit in your bathroom, you can prevent humidity from becoming condensation, maintain a comfortable temperature, and receive fresh outdoor air at the same time!

MVHR units are ideal for older homes that may not have been built to the same standard regarding insulation application. They are also ideal for anyone suffering from allergies. They are available in single-room and whole-house units, see our range here!.

Purchase a bathroom extractor fan today

Purchase a bathroom extractor fan today

At I-Sells, all things ventilation and ducting related is our speciality, we are here to answer the questions we know are common for those new to HVAC and what it encompasses.

We at I-Sells endeavour to ensure our customers have all the information they require before investing in our mould solutions. Be sure to visit our blog page to learn about the vast array of factors and issues surrounding ventilation, mould, condensation, and much more.

Within this blog, we hope to have shown you have answered the question, ‘Do I need an extractor fan in my bathroom?’, whilst providing you with supplementary information to help you, moving forward.

We understand you may have more questions, do not hesitate to contact us for more information about whatever you require our help with. If you’d like to email us, click here. For other contact options, see below:

Call us on 020 8463 9696

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15 St John’s Parade

Sidcup, Kent

DA14 6ES

United Kingdom

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