How to Install Roof Shingles – Valley Tip #1
Valleys fill up with water during a big shower and some water ends up under the shingles. If the shingle nails are too close to the center of the valley, you can get a leak. That nail pattern you see on the shingle wrappers doesn’t apply to the valleys. Keep your nails at least 12″ away from the center of the valley.
How to Install Roof Shingles – Valley Tip #2
Shingle seams can also leak when they fall right in the valley. Keep the seams at least 12″ away from the center of the valley by adjusting the length of the adjacent shingles on both sides.
Also check out this article on how to install roof shingles – here.
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