A vinyl gable vent is designed to ventilate stale air from the attic during the summer and prevent rain and snow from dripping through. Gable vents reduce heating and cooling costs.
Before installing the gable vent, remove any insulation that may be in the way with a utility knife.
Next, install the vent frame. Use boards to build a 2-by-4 square frame. Place the frame between the studs and the gable ends, and secure it with screws or nails. Factor in a 1 1/8 inch gap around the entire frame. When you are finished constructing the frame, drill 3/8-inch holes into the vent corners. These holes connect to the exterior of the house.
Mark the position of all of the holes with a pencil or piece of chalk on the roof, and connect the marks. This outline represents the vent opening. Saw along this line to cut out the opening.
Once the vent opening has been cut, see how the vent fits. If the vent fits straight, draw an outline for a flange. Use a circular saw to cut through the siding. Place the vent in the opening, and place the flange against the sheathing.
Finally, install flashing material around the vent opening. Flashing helps prevent water from seeping into the attic. Once the flashing is installed, lower the vent into place. Secure the vent with screws.