Install Circular Soffit Vents in Existing Siding

Circular soffit vents are easy to install in existing siding, which ensures that your home meets necessary ventilation requirements for maximum efficiency. Proper ventilation allows your home to be moisture free, and prevents ice buildup during the cold winter months. It also allows the heat of summer to escape the enclosed attic space. By installing additional ventilation, you will prolong the life of your roof, and decrease your utility bills, simply by increasing the airflow in your attic. 

You Will Require:

  • Pencil
  • Ladder
  • Soffit vents
  • Tape Measure
  • Screwdriver
  • Hammer
  • Rotary Tool

Step 1 - Preparing to Install your Circular Soffit Vents

Most circular soffit vents come in white and brown, as well as a few other common colors, that can be blended in with the home’s décor. The most common size is 2 inch, but there are many other sizes available as well.

Step 2 - Measuring for Circular Soffit Vents

Take a common stud finder, and mark off the rafter locations along the soffits of your home.  Start at the left hand side of your home, and place a mark between each of the rafters where the soffit vents will be installed. Spread them out evenly. Use a tape measure and measure the center between the 2 rafters, placing a line marking the center point. Then, measure between the house and the soffit edge and place another mark going the opposite direction, so that you create a crosshair, which will look like an “X.” This will pinpoint the location where the center of your hole will be positioned. 

Step 3 - Installing the Circular Soffit Vents

Because the soffit vent has a flange, they always come with a template to assist you with cutting the correct hole size. Using a pencil and the template, trace the hole for the vent, making sure to line the center of the template up to center of the “X”. Use the rotary tool to cut the hole out. Always begin by pushing the bit through the center of the hole, and then work your way out and around the circle, until you have completed the entire cut. Make sure that you have the correct bit installed into the tool, for the type of material that you have to cut through. Repeat this process until you have cut an opening for each circular soffit vent that you will be installing. Once you have cut all the openings, you can then push the round soffit vents into the hole, ensuring that the flange is flush with the soffit, and secure into place with the screws or nails provided.

Step 4 - Finishing the Circular Soffit Vents

In order to ensure that your vents are working correctly, go into your attic and pull the insulation away from the rafters, over the area you installed the new vents. Place an intermediate soffit vent, or a piece of 3 inch PVC pipe, to extend from the eave into the non-insulated area, which will allow for correct air flow. By doing this, you prevent the insulation from falling over the opening and blocking the airflow.