Want to know how a bathroom exhaust fan works? Read on, as we explain all...
If you’re new to bathrooms and all things that come with them, let’s start from the very beginning. Bathroom exhaust fans, more commonly known as “extractor fans”, are devices that remove moisture and odours from a bathroom. They do this by drawing air from the bathroom through a duct and to the outside of your property. The fan is usually mounted in the ceiling or wall of the bathroom.
That’s the basics over and done with, but why are they important?
Well, bathroom exhaust fans are important for several reasons:
- They help to prevent mould growth
Mould can grow in moist environments, such as bathrooms. When mould grows, it can release spores that can cause respiratory problems. Bathroom exhaust fans help to remove the moisture from the air, which helps to prevent mould growth.
- Bathroom exhaust fans help to improve air quality
When you take a shower or bath, things, naturally, get hot and steamy, releasing moisture into the air. This moisture can make the air in the bathroom feel humid and stuffy. Bathroom exhaust fans help to remove the moisture from the air, which improves air quality, making things far more pleasant for you.
- Bathroom exhaust fans can help to prevent the build-up of condensation
Condensation can occur when warm, moist air comes into contact with a cold surface. In a bathroom, this can happen on windows, mirrors and all manner of other surfaces. Bathroom exhaust fans help to remove the moisture from the air, which can help to prevent condensation.
You can find out more about how bathroom extractor fans work in our in-depth article.
Do you really need a bathroom exhaust fan?
To answer this question, you really need to have a long, hard look at your current bathroom setup. Indoor air quality is extremely important and, as already mentioned, a bathroom fan will help you with things like mould growth and condensation, not to mention ensuring your bathroom is properly ventilated.
If your bathroom is already well ventilated, with windows which can opened, a fan may not necessarily be required, whereas ventilating a windowless bathroom is a much more important matter. A bathroom doesn’t need windows, especially those that have been retrospectively added to a home, however, in such situations, bathrooms without windows need a good quality extractor fan.
Although not all buildings and bathrooms are required, by law, to install such a device, the benefits of having one in your bathroom are undeniable.
How to choose a bathroom exhaust fan
When choosing a bathroom exhaust fan, there are several factors to consider. However, probably the most important factors are:
- Size: The size of the fan should be based on the size of the bathroom. The fan should be able to exchange the air in the bathroom at least 8 times per hour.
- Sound level: The fan should be quiet enough to not be disruptive.
- Features: Some fans have features such as timers and humidity sensors. These features can be helpful in ensuring that the fan is running when it is needed most.
To get the best out of your bathroom fan, you need to ensure it is powerful enough for the size and usage of bathroom you have. The power of a fan should be stated in either m3/hr (cubic metres per hour) or l/s (litres per second), or sometimes both.
How to work out which bathroom fan I need using m3/hr
In the case of m3/hr, this shows how many cubic metres of air can be exchanged per hour. To work out which fan you need, you will need to know the volume of your bathroom and the number of air changes per hour (ACH) you want to achieve.
The volume of your bathroom can be calculated by multiplying the length, width and height of the room. For example, if your bathroom is 2 metres long, 1 metre wide and 2 metres high, the volume would be 4 cubic metres. The number of ACH you want to achieve will depend on the size of your bathroom and how often you use it. A good rule of thumb is to aim for 8 ACH.
You can use the following formula to calculate the m3/hr rating of the fan you need:
m3/h = (volume of bathroom in cubic metres) x (number of ACH)
So, for example, if your bathroom is 10 cubic metres in size and you want to 8 ACH you will need a fan with an m3/hr rating of a least 80.
How to work out which bathroom fan I need using l/s
In the case of l/s, this shows how many litres of air can be exchanged per second. To work out which bathroom extractor fan you need using litres per second (l/s), you need to know the volume of your bathroom and the number of air changes per hour (ACH) you want to achieve.
The volume of your bathroom can be calculated by multiplying the length, width and height of the room. For example, if your bathroom is 2 metres long, 1 metre wide and 2 metres high, the volume would be 4 cubic metres. The number of ACH you want to achieve will depend on the size of your bathroom and how often you use it. A good rule of thumb is to aim for 8 ACH.
Once you know the volume of your bathroom and the number of ACH you want to achieve, you can use the following formula to calculate the l/s rating of the fan you need:
l/s = (volume of bathroom in cubic metres) x (number of ACH)
So, for example, if your bathroom is 4 cubic metres in size and you want to achieve 8 ACH, you would need a fan with a l/s rating of at least 32.
How to install a bathroom exhaust fan
Installing a bathroom exhaust fan is a relatively simple process. However, it is important to follow the instructions that come with the fan. This should only be attempted by a qualified Trade professional.
- Choose a location for the fan. The fan should be mounted in the ceiling or wall of the bathroom. It is important to choose a location where the fan will not be blocked by furniture or other objects.
- Install the duct. The duct will carry the air from the fan to the outside. The duct should be made of a material that is resistant to moisture, such as PVC pipe.
- Connect the fan to the power supply. The fan should be connected to a dedicated circuit.
For more in-depth information, check out our complete guide to bathroom ventilation.
Shop bathroom exhaust fans
All in all, bathroom exhaust fans are an important part of a healthy bathroom. They help to prevent mould growth, improve air quality, and prevent the build-up of condensation. If you don’t have a bathroom exhaust fan already, you should consider installing one. To discover the full range of bathroom exhaust fans at Victoria Plum, simply click below.
