How to Install an Attic Ridge Vent

Climb onto the roof and carefully peel the shingles off the ridge cap to reuse on the new ridge vent. Peel away the shingles until you reach the gable end, but leave at least 8 to 10 inches of the old shingles near any wall or chimney.

Strike a chalk line 7/8 inches down from the peak of the roof on both sides of the ridge board at the roof peak, but if the roof has trusses, strike the lines so that it creates a 1-3/4 gap across the roof peak. Find the sheeting boards' edges at the roof peak.

Measure the thickness of the sheeting with a tape measure so that you can set the depth of the circular saw accordingly. Equip the saw with a carbide blade and adjust the settings. Cut through the shingles and sheeting using the chalk line you made on both sides of the roof but be careful not to cut through the rafters of the roof.

Separate the end of the woodcuts you made with a chisel and remove the wood you cut. Pry off the sheeting and pull out all the nails that are left in the rafters with a hammer. Attach all the new ridge vents with the long roofing nails. Make sure the nails penetrate completely through the vent, shingles, and the sheeting. Cover the new vents with the shingles that you pulled off at the start of the project or match new ones to the old shingles and secure them with roofing nails.

Climb down the ladder and go into the attic. If you have enough other vents installed, such as soffit vents, you should have adequate outflow air. Carry a pack of kitchen matches into the attic. Light one of those matches close to the new ridge vent and put it out quickly with your finger. Watch to see if the smoke exhausts through the ridge vent. If it doesn't, add more intake vents, such as soffit vents, to improve the airflow.