How to Apply New Roofing Shingles on Top of Existing Roofing Singles
- 1). Inspect the roof for damaged shingles that need to be repaired. Warped or bent shingles must be nailed flat or split in half. Missing shingles must be replaced.
- 2). Lay a starter strip along the eaves.
- 3). Cut the tabs off the whole shingles and measure up from the edge to match the exposure level (the amount of shingle showing) in the old roof. Nail the shingles in place so that the new row is even with the second row of the old roof. Make sure the adhesive strip is adjacent to the eaves. Cut and apply starter shingles along all of the eaves.
- 4). Butt the next row of new shingles up against the bottom of the old third row. If necessary, cut away any excess shingle height to match the exposure length of the previous roof. Cut enough of these shingles to run the length of the eaves.
- 5). Cut 5 inches off the rake side of the next new shingle and lay it up against the bottom of the fourth row of shingles, leaving a 3-inch exposure on the first row of shingles. Place a dab of cement under each shingle that sits on top of the first row.
- 6). Cut and apply shingle rows as normal for the new roof. The exposure levels will automatically match up with the previous roof as you progress.
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