A bathroom exhaust fan serves multiple purposes, but the main one is eliminating moisture from your bathroom. By eliminating moisture, you can prevent the bathroom from steaming up while showering, which prevents mould and mildew. If you have purchased a new exhaust fan for your bathroom, the first step to installation is fitting the fan into the ceiling.
Turn off the power to the area of the house where you will be working. Test the lights to make sure the electricity is off before making any cuts into the ceiling.
Drill a hole into the ceiling in the centre of the location where you would like to place the fan, using the pilot drill bit. The best placement for the bathroom exhaust fan is near, but not directly over, the shower.
Push a long piece of wire through the hole in the ceiling. Take the bathroom fan's housing with you and go into the attic. Locate the wire.
Remove the wire from the hole and place the fan in between the two nearest joists in the ceiling. Trace the fan's housing on the floor and cut out the opening for the housing in the ceiling material, using a saw or a utility knife.
Install the fan's mounting brackets according to the directions supplied with the unit. Lower the fan through the hole in the ceiling. Screw the mounting brackets to the joists on either side of the unit. Once connected, follow the manufacturer's instructions for attaching the fan to its housing and wiring the fan.
Shut off power to the bathroom. Double check that the electricity is off before cutting into the ceiling.
Locate the joists in the ceiling by using a stud finder or by repeatedly tapping a small nail into the ceiling with a hammer. Mark the joists on either side of the space where you want to place the fan.
Hold the fan's housing up to the ceiling so that it lies between two ceiling joists. Trace the fan's housing. Cut a hole for the fan into the ceiling with a saw or utility knife.
Push the housing up into the ceiling so that the bottom of the fan aligns with the ceiling. Drive screws through each hole in the sides of the fan housing, screwing them into the joists on either side to hold the housing in place. Once fitted, follow the directions provided to wire the fan and attach it to the housing.