- 1). Measure the lower edge of the roof. Divide the total length of the bottom edge by the length of your shingles to determine how many shingles you will need for your starter course.
- 2). Use a utility knife to cut the tabs off of all the shingles even with the top of the notches for the starter course. This will leave the strip of adhesive tar at the bottom edge of the shingle. The adhesive bonds the tabs on the first course to the roof and prevents them from lifting in high winds.
- 3). Cut six inches off of the left side of the first starter shingle with a utility knife. Place it on the lower left corner of the roof. Extend the left side and bottom edge of the shingle 1/2 inch over the edge of the roof.
- 4). Secure the first starter shingle to the roof with five evenly spaced roofing nails. The nails should be driven two to three inches up from the edge of the eave.
- 5). Measure the distance from the top of the starter shingle to the edge of the eave. Measure and mark this point on the right corner of the roof with a pencil. Use your chalk line to snap a straight line between these two points. You will use this as a guide to line up your starter shingles.
- 6). Line up and install the remaining starter shingles. Use the same nail spacing as on the first starter.
- 7). Place a full shingle on the lower left corner of the roof. Line up the lower and outer edges of the shingle even with the starter row. Secure the shingle with five evenly spaced roofing nails. The roofing nails should be placed at least one inch above the shingle's adhesive tar strip.
- 8). Measure the distance between the top of the shingle and the eave. Measure and mark this point on the right corner of the roof. Snap a chalk line from your mark to the top edge of the first full shingle.
- 9). Measure and cut six inches off of the left edge of the first shingle for your second row. Place it on your first row shingle. Line up the left edge with the outer edge of the roof. Place the bottom edge even with the top of the notches on the first shingle and nail it in place.
- 10
Cut one full tab off the first shingle for the third row. Place it over the top of the first shingle in the second row with the left edge aligned with the edge of the roof and the bottom edge in line with the top of the notches on the first second row shingle. - 11
Measure the distances between the tops of the shingles. Transfer and mark the measurements to the right side of the roof and snap a chalk line for each row. - 12
Install the remaining shingles in the first three rows. Working from left to right, install the shingle for the first row, then the second, then third. Repeat this process until you work your way to the right side of the roof. Trim the excess off of the shingles on the right side of the roof and repeat the steps above until you have reached the roof's peak. - 13
Apply a peak cap by cutting the three-tab shingle into three single tabs. Center the tab over the edge of the roof peak with the adhesive strip away from the edge. Secure the tab with one nail on each side of the peak. Overlap each consecutive tab allowing five inches of exposure for the previous tab and nail in place. Continue until you reach the opposite edge of the roof. Cover the holes in the final tab with roofing asphalt adhesive.
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