How to Install a Window Exhaust Fan

A man installs a window exhaust fan.
  • 5-10 hours
  • Advanced
  • 50-500
What You'll Need
Piece of Lexan
Glass cutter
Exhaust fan
What You'll Need
Piece of Lexan
Glass cutter
Exhaust fan

Using a window exhaust fan can help you cool down your room without the use of an air conditioner. While they do not work as well as an air conditioner, they are not as expensive to operate.

A window exhaust fan is used to evacuate the hot, humid air out of a room to make it more comfortable. This is the effect of cooling down a room. Installing the window exhaust fan is not a hard project, but does require some work with glass.

An exhaust fan should not be confused with an ordinary window fan. The window fan is used to circulate air from the outside into the room for a cooling effect. The window exhaust fan is used to drive the air out of the room.

Step 1 - Remove the Window Pane

Before you can install an exhaust fan into a window you will need to remove the window pane. This can be done easily if you are working with a double pane window. Simply remove it from the casing.

Step 2 - Replace Glass with Lexan

If you try to install the window exhaust fan into a pane of glass, you run the risk of cracking the glass and having to replace it anyway. Lexan is a strong material that can be used as a replacement for the glass that you can see through and clean very easily.

Step 3 - Outline Exhaust Fan onto Lexan

Using the casing of the exhaust fan as a guide, you can trace the outline onto the center of the Lexan piece. Make sure that the case is level before you start to draw on the Lexan material.

Step 4 - Cut Out Hole for Fan

There are two ways that you can cut the Lexan material for installing the fan. The first way is to drill a hole in the corners and cut with a jig saw. This can cause some splintering of the material. Another way is to score it with a glass cutter and tap out the piece when you can score it several times. This will leave a clean cut without any ragged edges.

Step 5 - Replace Window

Once the hole has been cut, and the Lexan has been installed, you can now replace the window back into the casing.

Step 6 - Install Fan

With the window back into the casing, you can install the exhaust fan. Remove the front cover of the fan so you can easily slide the motor into the casing.

Step 7 - Drill Holes for Screws

Set the case back onto the Lexan and mark for the holes that are for the mounting screws. Remove the case and drill the holes with a cordless drill. Be careful and drill straight into the Lexan and not to the side.

Step 8 - Mount Case

Set the case back onto the Lexan and screw in the bolts from the outside. Use the locking nuts to secure them into position.

Step 9 - Set Fan in Case

With the case mounted, set the fan inside and secure with the retaining screw. Place the cover over the fan and plug into the the closest outlet.