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A good 100mm bathroom extractor fan helps remove moisture, steam, and unwanted odours before they can cause condensation or mould. Whether you’re replacing an old fan or fitting one in a new bathroom, choosing the right model can improve ventilation while keeping noise levels to a minimum.
We’ve compared the best 100mm bathroom extractor fans available in the UK, considering airflow, noise, features, ease of installation, and overall value.
1. Airflow iCON 15 100mm Bathroom Extractor Fan
The Airflow iCON 15 is a stylish 100mm extractor fan designed for bathrooms, en-suites, and cloakrooms. Its standout feature is the unique iris backdraught shutter, which closes automatically when the fan is switched off to help prevent outside air, draughts, and unwanted noise from entering your home.
Key points:
- 100mm (4-inch) extractor fan
- Airflow: 19 l/s (69 m³/h)
- Ultra-quiet 28.8 dB operation
- Unique iris backdraught shutter
- Wall or ceiling installation
- Optional timer, humidity and PIR modules
- IPX4 rated for bathroom use
- Low 9.4W power consumption
- 3-year manufacturer’s warranty
2. EnviroVent SIL100 Silent 100 Bathroom Extractor Fan
The EnviroVent SIL100 Silent 100 is a powerful 100mm extractor fan that combines high airflow with impressively quiet operation. Extracting up to 96 m³/h (26 l/s), it’s well suited to bathrooms, shower rooms, and WCs where effective moisture removal is essential.
Key points:
- 100mm (4-inch) extractor fan
- Airflow: 26 l/s (96 m³/h)
- Quiet 26.5 dB operation
- Adjustable run-on timer
- IP45 rated for bathroom installation
- Suitable for wall or ceiling mounting
- Low 8W power consumption
- Compatible with 100mm ducting
- CE approved
3. Xpelair DX100BTS Simply Silent 100mm Bathroom Extractor Fan
The Xpelair DX100BTS Simply Silent is a compact 100mm extractor fan designed to remove moisture, steam, and odours while keeping noise to a minimum. Featuring Ghost Air Movement technology, it operates quietly, making it a great choice for bathrooms, en-suites, WCs, and shower rooms.
Key points:
- 100mm (4-inch) bathroom extractor fan
- Adjustable twin-speed airflow (15 or 21 l/s)
- Up to 76 m³/h extraction rate
- Adjustable run-on timer
- Wall or ceiling installation
- IPX4 rated for bathroom use
- Compact, lightweight design
- 1-year manufacturer’s warranty
What Actually Matters
A 100mm extractor fan may look like a simple appliance, but there are several features that affect how well it performs in everyday use.
Extraction Rate
The extraction rate shows how much air the fan can move and is usually measured in cubic metres per hour (m³/h) or litres per second (l/s). Bathrooms with showers generally benefit from a higher airflow to remove moisture more quickly.
Noise Level
A quieter fan makes a noticeable difference, especially if it’s used during the night. Many modern 100mm extractor fans operate below 30 dB, making them much less intrusive than older models.
Timer Function
A timer allows the fan to continue running for a few minutes after the bathroom light has been switched off. This helps remove any remaining moisture and reduces the risk of condensation.
Humidity Sensor
Some extractor fans automatically switch on when humidity levels rise. This is particularly useful in busy households, as the fan runs only when needed.
Installation Type
Most 100mm extractor fans can be fitted in a wall or ceiling, but it’s important to check the manufacturer’s installation requirements before buying.
IP Rating
Bathroom extractor fans should have a suitable IP rating to protect against moisture. A higher rating provides better protection in damp environments.
How to Choose the Best 100mm Bathroom Extractor Fan
Before buying, consider where the fan will be installed and how often your bathroom is used.
Bathroom Size
Small bathrooms usually require less airflow than larger bathrooms or en-suites with powerful showers. Choosing the correct extraction rate helps remove moisture efficiently.
Choose the Right Features
A basic on/off fan is suitable for many bathrooms, but timer, humidity sensor, and motion sensor models provide greater convenience and can improve ventilation.
Consider the Noise Level
If your bathroom is close to a bedroom, choosing a quieter extractor fan can make a noticeable difference during early mornings and late evenings.
Installation Tips
Installing a 100mm extractor fan is relatively straightforward when replacing an existing unit with the same size. Always isolate the electrical supply before beginning any work.
Position the fan as close as practical to the main source of steam, such as above the shower or bath, while following UK electrical safety regulations for bathroom zones. If you’re installing a new fan or making electrical connections, using a qualified electrician is recommended.
Is a 100mm extractor fan powerful enough?
Yes. A 100mm extractor fan is suitable for most bathrooms, en-suites, and cloakrooms. Larger bathrooms may benefit from a higher-capacity model.
Should I choose a timer or humidity sensor?
Both are useful. A timer keeps the fan running after you leave the room, while a humidity sensor switches the fan on automatically when moisture levels increase.
How noisy is a modern extractor fan?
Many modern 100mm extractor fans operate between 16 and 30 dB, making them much quieter than older models.
Do bathroom extractor fans use much electricity?
No. Most modern extractor fans consume very little electricity, making them inexpensive to run even with regular daily use.