Fan Size Selector

Why Vent - Types of Fans - Siting the Fans - Ducting - Data Sheets

Suggested Size Fan - Calculator - ( see notes below )

For a second fan selector based only on the building regulations and excludes Air Change Rates click here.

Results reflect

Building Regulations Part F 1995 England Wales

minimum size fan allowed ( extract Table 1 ) - to see official ventilation regulations

  1. Bathroom - 15 litres / second
  2. Kitchen - 60 litres / second
  3. Kitchen - 30 litres / second if within cooker hood or 300mm of a hob
  4. Utility Room - 30 litres / second

In rooms with no natural light it would be appropriate for the fans to be controlled by the operation of the light switch.

Excludes:

Loss of pressure from the use of ducting see Ducting

Dwellings with open-flued combustion appliances ( Gas / Oil or Solid fuel ) see Notes

Recommended Room - Air Change Rates

Domestic We researched various
British manufacturers
who's range of recommended
room air rate changes are listed below
Room Rate Used
In Shower Area 15 - 20 20
Bathroom & Shower Rooms 15 - 20 15
Bathroom 6 - 10 8
Bedrooms 2 - 4 4
Halls & Landings 4 - 6 5
Kitchens 10 - 20 15
Living & Other Domestic Rooms 4 - 6 5
Toilets - Domestic 6 - 10 8
Utility Rooms ** 15 - 20 15

**Utility room means a room designed to or likely to be used to contain clothes washing and similar equipment such as a sink, washing machine, tumble dryer or other feature or equipment which may reasonably be expected to produce water vapour in significant quantities.

Commercial

Caf├ęs 10 - 15 15
Canteens 8 - 12 10
Cellars 3 - 10 6
Changing Rooms with Showers 15 - 20 15
Conference Rooms 8 - 12 8
Garages 6 - 10 8
Hairdressing Salons 10 - 15 13
Hospital Wards 6 - 8 7
Laundries & Launderettes 10 - 15 13
Meeting Rooms 6 - 12 7
Offices 4 - 6 6
Restaurants & Bars 10 - 15 12
School Rooms 5 - 7 6
Shops 8 - 10 9
Sports Facilities 4 - 6 6
Rooms 5
Workshops 6 - 10 8

For more commercial room air rate recommendation