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Valley

A valley is the area where two roof planes meet and water concentrates.

Waterproofing and Building Envelope

Why it matters

Valleys handle a lot of water. Poor valley details cause leaks fast.

Where people get this wrong

A valley is not just shingles. It needs a specific water management detail. Debris buildup can make a good valley act like a bad one.

Real-world example

Leaves pile in a valley and water overflows during storms. That water finds the weakest seam and you get a leak.

Where this hits your build

This affects how your home handles water. Water damage is one of the most expensive problems to fix, and it often starts with details that seem small.

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