Bathroom Air Vent Installation

Bathroom Air Vent Installation

Vent your bathroom fan outdoors to avoid costly repairs later

By Robert Ferguson

Installing vent outside house
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Direct the exhaust from a bathroom fan to outside your house either through a vent in the wall or a vent installed on the roof. When exhaust is allowed to vent into the attic, mold can develop, and the moisture can rot the wood, causing costly repairs down the road. Directing the exhaust through the roof avoids these types of problems. With a moderate set of home improvement skills, you can complete this project in about a day.

  • What You Need to Know
  • There are a few elements you'll need to install a bathroom air vent successfully. These include extension tubes, exhaust fan duct tape, a drill, caulk gun, screws, screw gun and putty knife.

Step 1:

Locate the area on the roof that is suitable for vent installation. Do this from inside the attic to avoid trusses and beams. Locate the vent as close to the exhaust fan as possible. Avoid roof valleys, hips and ridges for vent installation.

Step 2:

Mark the area between two trusses with a pencil or marker where the vent will be installed, using the vent's tube as a reference. Trace the outline of the vent's tube on the roof or attic ceiling.

Step 3:

Drill a hole through the roof inside the circle that was marked on the ceiling.

Step 4:

Using a reciprocating saw or jigsaw, cut out the tube's outline on the roof or attic ceiling.

Step 5:

Lay the roof vent on the roof over the hole and trace the outline on the roof using a pencil, then set aside. Insert a tube of roof cement into the caulk gun. Apply the roof cement generously to the roof inside the vent's outline.

Step 6:

Install the vent from the outside. Fasten the vent's tube to the vent, using duct or foil tape. Slide the tube through the hole in the roof and press down firmly, while making sure the vent seats tight and flush to the roof.

Step 7:

Use a screw gun and drive screws through the vent's base into the wood under the roofing materials to secure the vent. Use the putty knife to wipe the excess cement around the vent seams, making sure there is adequate cement all the way around to seal the vent to the roof.

Step 8:

Apply roof cement to the screw heads securing the vent. Make sure the screws and the seam are sealed with the roof cement.

Step 9:

Install the exhaust fan's duct tube to the roof vent's extension tube, extending through the roof into the attic. Use duct or foil tape to secure.

Step 10:

Use roof cement to caulk around the seam between the vent's tube and the roof's wood.

  • Tips & Warnings
  • Use caution when working in attics.
  • Use a dust mask or respirator when working in attics.
  • Watch out for sharp objects like nails when working in attics
  • Use caution when working on rooftops.
  • Use caution when working with power tools.

About the Author

Robert Ferguson is a licensed building contractor with more than 30 years of experience, focusing primarily on residential remodeling, repair, renovation and construction.

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