Extractor fans#
Extractor fans are necessary in some spaces to remove moist or stale air, but they also cause heat loss. You probably have them in kitchens and bathrooms, but you may also have them as ventilation in other areas. The cheapest ones have an on/off switch and can be wired to the same switch as the lights. If the switch gets left on, you are venting what might be warm air, and if people are only in the space for a short time, they might not be on long enough to keep the space dry.
There are two things to consider.
Changing the fan control. Fans can come on with the lights but run longer, work from a pull cord, or run automatically based on the relative humidity. The right choice depends on the application.
Change for heat recovery extractor fans. These recover the heat from the exiting air and put it back into the building by transferring it to fresh air from outside.
You should definitely consider this action when the fan needs changing anyway, but in frequently used spaces or ones with damp problems, it may be worth considering earlier than that.
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