domus - the complete solution - CMS

A GUIDE TO VENTILATIONFAN SELECTIONThe extraction rates recommended by the UKBuilding Regulations should be seen as theminimum requirement. A more accuratemethod of calculating the optimum rate, or ifthe room to be ventilated is not covered bythe Regulations, is as follows:1. Measure the length, breadth and heightof the room (in metres) and multiply themtogether to obtain the room volume in cubicmetres.2. Multiply the room volume by therecommended number of air changes perhour, shown on the table, to achieve theextract rate of the fan in m 3 /hr.3. Select a fan with a duty the same as, orexceeding, the calculated extract rate.eg: Bathroom 2.5m x 2m x 2.3m x 8 ach =92m 3 /hr.Fan selected: T1/T1R extracting 94m 3 /hr.RoomAirchangesper hourBathrooms 6 - 8Bedrooms 2 - 4Billiard Rooms 6 - 8Cafes and Coffee Bars 10 - 15Canteens 8 - 12Cellars 3 - 10Club Rooms 8 - 10Conference Rooms 6 - 10Entrance Halls, Corridors 3 - 5Factories and Workshops 6 - 10Garages 6 - 10Gymnasiums 6Hairdressing Salons 10 - 15Hotel Bars 6 - 10Kitchens - Domestic 10 - 15Laboratories 4 - 15RoomAirchangesper hourLaunderettes 10 - 15Laundries 10 - 15Lecture Theatres 6 - 10Libraries 3 - 4Living Rooms 4 - 6Offices 4 - 6Photo and X-ray Darkrooms 6 - 8Public House Bars 6 - 8Restaurants 10 - 15School rooms8.3 l/s/PersonShops and Supermarkets 8 - 10Shower/Bathrooms 15 - 20Stores and Warehouses 3 - 6Toilets (Public)5+ or 6 l/s/PanToilets (Domestic) 6 - 10Utility Rooms 15 - 20PROBLEMS AND SOLUTIONSEnsuring air quality of the highest standardsignificantly reduces the problems caused bydamp, condensation and unwanted smellsthat may prove a risk to the inhabitants orstructure of a building.Inadequate ventilation can cause manyproblems:• Condensation.• Dampness and potential mould growth.• Unwanted kitchen smells throughoutthe house.• Old and stale air remaining in the buildingresulting in a lack of new, fresh andhealthy air.These problems create a building that has anunpleasant living environment. However,appropriate action can be taken.• Always turn the fan on before bathing,taking a shower or cooking.• Always close internal doors leading toother parts of the building.• Always allow a buffer zone after bathing,showering or cooking by keeping the fanturned on for a short period of time.• Always fit the correct size of ducting toensure maximum performance of the fan.The following pages are designed togive guidance on general ventilationducting installation.5