Bathroom Fan Guide

A guide to choosing your Bathroom fan

Any bathroom, en-suite, toilet etc are required to adhere by the building regulations, which means that any new build or other work that requires planning permission will have to have a fan. Also any bathroom etc. should have in it since these areas are where there is a large amount of moisture that can cause mold growth. Thus we know the need for a fan but what fan is the question.

We offer two Helios extract fan ranges:-

MiniVent® Eco GreenTec Range UltraSilence® ELS
Mix & Match Range
 Eco Extract Fans  Helios Ultraquiet ELS Extract Fan
 More Info  More Info

What are the Regulations?

The building regulations Document F state that for continuous ventilation there should be at least 8 litres per second airflow out of the room. In the case of intermittent ventilation then 15 litres per second is required. So first decide if you require a fan that is only used when the room is in use or on continuously..

Key Choices:

  • Speed? 35m3/h to 120m3/h (10 l/s to 33.3l/s)
  • Normal or Ultrasilent® operating sound
  • Whether the fan runs on for a period of time after you turn off the light
  • Whether the fan is operated by a motion sensor PIR
  • Whether the fan is operated by a dynamic humidity sensor
  • The position of the fan (SELV) for splash areas
Some fans offer a combination of the above including trickle and boost for continuous ventilation. Whatever your answer to these choices we have the fan for you in one of our ranges.

The position of the fan is important and the regulations BS 7671 specifies the level of protection required for positions in the room defined by zones. Many fans can not be placed in Zone 1, Above the bath or shower, as they do not meet the requirements of IPX4. All the fans offered here are at least IPX4 and can be used in zone 1 (also zone 2 ) of the bathroom. Zone 1 includes above the bath and above the shower above a height of 2.25 metres above the floor. An alternative option for zone 1 is Safe Extra Low Voltage (SELV) fans. All the bathroom fans offered here are also suitable for all Zones except zone 0 which means these fans ca be mounted above the the shower or bath but not in the splash areas of the shower or bath. We also offer SELV (safe extra low voltage) fans should this be required or specified.

There many choices of the way in which the fan is operated. In the case of continuous ventilation we select a fan for the 8 litres a second but may also add a boost when occupied. In the case of intermittent ventilation the building regulations require 15 minutes run on time. This means that when the room is no longer occupied the fan must then run for a further 15 minutes to clear the air before switching off. There are several automatic ways of ensuring that the fan comes on when required and runs on if necessary.

The appearance of the fan can also be important.

If you have any questions about which fan is best for you please contact us