Installation of round soffit vents begins by calculating the total area of the attic space. Mark the spots for placing soffit vents, and cut away the insulation on the soffit overhang that can block the vents. Center the soffit vent over the hole, and secure it using a hammer and nails.Continue Reading
Multiply the length and width of the space to get the total area of the attic space. Determine the space that requires venting in total square feet by dividing the total area by 150. Divide the square feet of venting by 2 because half of the venting Is given by the ridge while the other half is given by the soffit vents.
Calculate the area of each soffit vent using the formula for finding the area of a circle. Convert the answer into square feet by dividing it by 144. Divide the soffit vent area by the area of the attic space to get the total number of soffit vents needed.
Mark where you want to place each soffit vent, and space them evenly with all vents lining up vertical to the roof vents. Inspect and cut away any insulation on the soffit that can block the vents. Cut a hole into the soffit, and apply a bead of caulk to the flange area of the soffit vent. Place the soffit vent at the center of the hole, and secure it using a hammer and nails.