How to Install an Asphalt Shingle Roof
- 1). Remove any old roofing materials and repair loose or damaged sections of roof sheathing. Make sure all flashing materials are in place. Cover the entire roof surface with felt or waterproofing membrane. Choose a waterproofing material compatible with the shingles you plan to use.
- 2). Nail edge flashing to the eaves of the roof. Use 1 1/4-inch galvanized nails if you are installing directly to the roof sheathing, or 1 1/2-inch nails if you are working over existing asphalt shingles. Place nails roughly 3 inches above the eaves of the roof.
- 3). Cut the tabs off a shingle to create a starter strip. This starter strip reduces moisture infiltration under the first row of shingles. Place the shingle face down on a flat surface and cut using a utility knife and a straight edge. Nail this strip so that it overhangs the roof edge by 1/4 inch. Repeat this process along the entire bottom row of roofing.
- 4). Begin installing shingles starting along the lower corner of the roof. The bottom of the first row of shingles should overlap the starter strip completely so that it also overhangs the eaves by 1/4 inch. Place nails slightly above the tar line in each shingle.
- 5). Install each remaining row so that the tabs overlap the tar line of each shingle by about 1/16 inch. As you start each row, cut each shingle to a slightly different width so that the tabs will not align with those on other rows. This helps keep moisture from penetrating below the shingles.
- 6). Continue installing shingles so that you overlap the hips and ridge line. Nail the shingles along the ridge line so that they curve over the ridge and cover them with ridge cap shingles designed to fit the profile of your roof.
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