How to Replace Roof Ridges

Loosen the old ridge shingles, starting on one side of the roof and wedging the flat end of a nail bar beneath the bottom lip of the shingles. Pry upward carefully to remove the shingles in one piece, if possible. Repeat on the other side. The ridge shingles might stick together, coming off in a single unit.

Remove any roofing nails that remain beneath the old shingles with the nail bar. Scrape off stuck bits of shingles, if necessary, but do not gouge the shingles still on the roof.

Break hip and ridge shingles apart along perforated lines. The shingles come in sections that are 3 foot long and 12 inches wide. Each section contains three 12-inch-by-12-inch ridge shingles.

Measure 6 inches down from the roof ridge on both sides of the roof, and snap a chalk line on each side that extends from side to side. These are the guidelines for installing the ridge shingles.

Start at one eave, which is at the very edge of the roof and position a ridge shingle so its outer edge is even with the outer edges of the existing shingles. The thin asphalt strip in the middle of the shingle should fold over the top of the ridge.

Insert a 1 1/2-inch roofing nail on one side of the shingle, about 1 inch up from the bottom edge and 5 1/2 inches from the starting edge of the shingle. This will put the nail right beside the asphalt strip, but not on top of it. Some ridge shingles have a nailing line, which makes it easier to position the nail in the right spot.

Nail the shingle on the other side of the roof in the same manner and then put another shingle directly over the first one. The starting shingles are doubled to add strength at the edges of the roof, which helps the ridge shingles resist damage from strong winds. Attach the double shingle in the same way, but move the nails about 1/2 inch upward to avoid hitting the first nails.

Position the next ridge shingle so it covers the nails on the previous shingle, leaving 5 inches of the previous shingle exposed. Check the bottom edges of the shingle to ensure that they match with the chalk lines and nail on both sides as before.

Continue adding shingles, overlapping each new one in the same manner until you near the middle of the roof ridge. Stop and then begin installing shingles from the other end of the ridge, working toward the middle.

Install a shingle on each side, one at a time, until you’re ready for the center shingle, which must overlap the shingles on both sides.

Position the final center shingle, folding it over the two side ridge shingles and use four nails, two on each side to secure it. Each nail should be 1 inch up from the bottom and 1 inch in from the outer corner of each shingle. These four nails will be the only visible nails.