How to Install a Bathroom Exhaust

Decide where in your bathroom you would like to install the exhaust fan. It does best when located between the tub and the toilet. Use a long 3/8-inch spade bit to drill through the chosen spot.

Measure the inside diameter of the fan housing. Mark these measurements with a layout square on the ceiling where you will be placing the grill.

Cut out the hole you marked in Step 2 with a reciprocating saw.

Connect a 4-inch round duct elbow to the outlet port in the side of the fan housing. Position the elbow so that it forms a 90-degree angle and is pointing straight up. Wrap foil duct tape around the edge of the elbow and the housing.

Knock out the cutout on the opposite side of the housing with a hammer. Place a cable connector in the hole.

Slide out the metal brackets on each side of the fan housing. Center the housing over the hole you cut out and lower it down between the trusses. Screw the lips of the metal brackets to the side of the trusses with a 1/2-inch drywall screw to hold the vent housing in place.

Place one end of the flexible duct from the vent kit over the 90-degree elbow. Use foil duct tape to hold it in place. Put the electrical cable through the cable connector and tighten the connector screw.

Attach the other end of the flexible duct to the wall cap, located either in the side of the house or the roof. Wrap foil duct tape around this connection to hold it in place.

Remove the screws holding the blower fan in place. Unscrew the receptacle underneath to expose the wiring.

Connect the black wires with a wire nut and the white wires with a wire nut. Bend the end of the bare wire into a "U" shape and wrap it around the green screw on the side of the housing.

Screw the receptacle back in place. Lift the motor back into the ceiling and plug it into the built-in receptacle. Replace the screws you took out in Step 9.

Attach the grill's mounting wires to the slits in the side of the housing. Push it up until it is tight to the ceiling.