When you install one year 50 (composit shingles) roof, and you install valleys metal valleys should have openings on both sides to allow free flow of water? Or perhaps these valleys closed or covered with shingles? I was told two different answers from roofers and would like to know what the standard of the industry. Please notify
Your 50 year shingle only keep water if properly installed, galvanized tin or aluminum valley is a additional security. Cover it with shingles, it will do much better.
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