Attic Ventilation: Installing Soffit Vents

The corner of a roof, with shingles, gutter, and eaves visible.
  • 5-10 hours
  • Intermediate
  • 100-300
What You'll Need
Soffit vents
Safety goggles
Safety gloves

Soffit vents are essential for proper attic ventilation. These vents, also known as under-eave vents, are the best way of getting cool air into the attic. If you have a fairly modern house, you likely already have soffit vents in conjunction with your gable or ridge vents.

Some old homes do not have them. If you have an older house that is not yet fitted with soffits, you should consider fitting these into your home. Installation is easy. Basic knowledge of home improvement is all you need.

Step 1 - Prepare the Installation

Before you begin to install your soffit vent, you need to do two things. First, check that the area where the soffit will be installed is free of insulation. If you find any in the roof, move it, remembering to wear safety gloves and a particle mask. Clear the area and then mark out a place where the vent will not interfere with joists, boards, and other roof furniture.

Once you have this organized, pick out a suitable soffit. They come in plastic and metal, as well as wood. Aluminum vents can be painted to match the rest of the house, whereas plastic vents typically only come in brown or white.

Step 2 - Make Your Holes

Once you have a suitable vent, it's time to cut the holes. Measure your vent and then cut a space in the eave slightly smaller than that, so your attic vent will fit snugly.

To do this, use a square edge to make sure the holes are all suitably even and then drill small holes along the length of the area where your vent will go. Use your saw to make these holes into lines until the square of ceiling falls away.

Step 3 - Install the Vents

Now, take the screws included with your vent and use the drill to screw one into each corner. After that, add additional screws into the center of each side. Once all the screws have been installed, go back and tighten them all until they hold the vent firmly in place.

Step 4 - Apply Caulk

Once you have fitted the vent, take a putty knife and place some caulk around the edges. This will help seal the vent against drafts, which can otherwise enter your living space and cause heat loss. Leave the caulk to dry naturally for a day or so.