Pay careful attention to the corner details. Install your next row of shingles over that first step flashing, then cowl that row with a step flashing, and so forth. Nail the step flashing to the wall towards the top of the flashing on the finish that is nearer to the peak, so the next step flashing in line will cowl the nail. For details about flashing around chimneys, see Installing Chimney Flashing. For good straight traces, run shingles over the sting of the roof. Then snap a chalk line and trim them off with a hook blade in your utility knife.
The shingles are woven together from both sides of the valley. The benefit of a woven valley is that it does not go away an exposed flashing, which results in a cleaner look. The downfall is that leaves and twigs don’t get washed away as easily, which may cause little water dams. This is particularly true for roofs with low pitches.
Use a tin snips to chop the drip edge to measurement. Make positive this row has a slight overhang (1/four to 3/8 in.) beyond the drip edge. The starter course protects the roof by filling within the spaces underneath the cutouts and joints of the next row of shingles.
If the overhang is greater than a foot, cut some off and use the remainder elsewhere. Another means of coping with valleys is to make use of the “weave” technique, which we don’t cover in this story.
The adhesive on the starter course seals the tabs of the primary full course. Install the top ridge cap so the prevailing winds blow over the overlaps quite than into them. If wind is not a problem, start at both aspect, or start at each side and end within the middle. Rip the top half off the last ridge cap shingle, and nail through the face of it with two nails on the ends of every side. Weave the step flashing and the roof shingles collectively so that water cannot get underneath the shingles.
When you reach the top of the roof, run your final row long , and drape the paper over the peak onto the other facet. When you attain the highest on the opposite aspect of the roof, run that paper up and over as properly. That method you will find yourself with a watertight ridge. Your native constructing official might want to come out to examine your roof at this level, however sometimes you will get by with snapping a number of pictures. Ask about the inspection schedule if you pick up your permit.