TL;DR
Valley flashing is the metal channel installed where two roof planes meet at an inward angle, carrying the concentrated runoff of both slopes down to the eave. Open valleys use 24-inch-wide painted steel, aluminum, or copper, often with a W-shaped center rib that keeps cross-wash from one slope running under the shingles of the other, over an ice-and-water membrane below.
What it means
Valley flashing is the metal channel installed where two roof planes meet at an inward angle, carrying the concentrated runoff of both slopes down to the eave. Open valleys use 24-inch-wide painted steel, aluminum, or copper, often with a W-shaped center rib that keeps cross-wash from one slope running under the shingles of the other, over an ice-and-water membrane below. Closed and woven shingle valleys skip the exposed metal, but in snow country and on long valleys the metal detail outlasts them, and valleys are among the first places roof leaks actually start.
Where it sits in the glossary
Valley flashing is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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