In your home there are particular rooms that are prone to problems created by localised humidity namely the Kitchen, Bathroom and Laundry.  The steam created by cooking, hot water and clothes dryers can have an effect on the climate within your home.  If left to build up the moisture can start to affect the walls and ceiling by creating mildew and mould.  An exhaust is a simple solution to this problem.

 

An exhaust fans work by sucking hot or humid air out of a small, localised area, allowing fresh air to enter from elsewhere (perhaps a doorway or vent) in order to replace it. The warm air that's drawn out using an exhaust fan is then pulled through a ducting system and expelled outside.  

 

Careful thought into the location of an extraction fan will ensure maximum air-flow through the room.  Extracted air from a room can be replaced with fresh, dry air drawn from an adjacent hallway, a window, vent or grille in a door or exterior wall.  It is important to position the exhaust fan opposite the source of in-flowing air to encourage a cross-breeze which is essential to clear vapour and odours.

 

Switching on the exhaust fan before showering, cooking or using the clothing dryer will start the air-flow before the associated condensation problems occur.

 

For an exhaust fan to perform at maximum efficiency, it's vital that the exhaust fan has access to a balanced airflow.  Opening a door or a window will help remove the moisture and steam from your bathroom.

 

You must ensure that there is adequate room in the ceiling for the steam to dissipate.  If you have restricted space in your roof cavity then you should use a ducted exhaust fan.  It is important not to position an exhaust fan too close to a door/window as this will provide air circulation at the door/window but have little or no effect on the rest of the room.