How to Install Automatic Foundation Vents on Your Home

Most old metal foundation vents are equipped with a lever or slide switch which allows the homeowner to manually open and close the vents in response to changes in the temperature outside. Let's face it though, how many people remember to switch these vents at the appropriate times? Leaving the vents open year-round wastes energy and can lead to excess moisture under a home.

This creates a perfect environment for mold and mildew to grow and is also a welcome home for termites. Automatic foundation vents are a wonderful investment because they save the homeowner the trouble of having to constantly open and close them with the changing outside conditions.

Most automatic foundation vent installations require only a claw hammer and a flathead screwdriver. Using a pair of knee pads will make the job more comfortable.

To remove an existing foundation vent, the cement around the vent needs to be chiseled away. Strap on your knee pads or position your stool in front of the vent to be replaced and use the hammer and either a chisel or a flathead screwdriver to tap on the cement around the existing vent. Most of it should crack and fall away. Be sure to only loosen the cement around the vent and try not to loosen any of the bricks.

If the existing foundation vent is made of metal, try to wedge the claw portion of the claw hammer behind one of the metal slats on the face of the vent. Now use some leverage to pry the vent out of the wall. Don't worry about damaging the vent. It should be discarded at the end of the project anyway. When the vent is removed, use the hammer and chisel or screwdriver to remove any excess cement in the rectangular opening left by the absent vent.

Installation may vary depending by the type of automatic vents that you purchase, but the current standard uses metal clips and also pointed screws which apply pressure to the bricks at each corner of the automatic vent to hold it in place. Position each clip and screw in place and then, working against the resistance caused by the metal clips, insert the automatic vent into the opening. Once it is flush with the existing brick wall, tighten each screw carefully.

That's it, the installation is complete. When the temperature drops to approximately 40 degrees F, the vent will close automatically using an internal metal coil. This same coil will cause the vent to reopen when the temperature returns to 70 degrees F. There are powered vents available which include a fan, but these simple automatic vents only use a metal coil and no power to operate.

Tips & Warnings 

• Routinely inspect under your home for signs of moisture.
• Be sure to maintain a contract with a termite control company. They will alert you to possible moisture problems when they perform the annual termite inspection.
• If you cannot afford to purchase replacement vents for your entire house at once, try replacing just several at a time every few weeks.
• Automatic foundation vents may be found at your local home improvement store and the average price is around $15 each.
• Do not assume that just replacing vents will completely solve moisture problems under your home. This is just one remedy. Each situation is different. Evaluate your situation carefully and if you need automatic vents, then the steps in this article will help you to install them.
• Avoid striking the bricks around the vent opening or applying too much pressure. You'd be surprised how easily they may be removed!