How Do You Reroof Over Existing Shingles?
In many cases it is possible to reroof over existing asphalt shingles. It will depend on the structural integrity of your building and whether or not the building’s structure can carry the additional weight. It also depends on local building codes. The steps to install over existing shingles are virtually the same as installing shingles over a bare roof. Inspect the roof. Look for any protruding nails and drive them back in. Remove any warped or buckled shingles. Begin at the edge of the roof. Install the first row of shingles so that the unnotched edge is flush with the edge of the roof. Secure the shingle with three nails. Place the nails near the edge of the shingle opposite the edge of the roof. Butt the side of the next shingle against the edge of the first shingle you installed. Secure with nails. Continue until the first row is complete. Install second and subsequent rows. These shingles are all installed with the notched edges toward the edge of the roof and the straight, unnot
