TL;DR
Window head flashing is the formed metal or rigid drip cap installed above a window's top trim, tucked up behind the siding and water-resistive barrier so any water running down the wall is kicked out over the window rather than behind it. The barrier must lap over the flashing's vertical leg, shingle-style, for the assembly to drain; taping the bottom edge or relying on caulk alone defeats it.
What it means
Window head flashing is the formed metal or rigid drip cap installed above a window's top trim, tucked up behind the siding and water-resistive barrier so any water running down the wall is kicked out over the window rather than behind it. The barrier must lap over the flashing's vertical leg, shingle-style, for the assembly to drain; taping the bottom edge or relying on caulk alone defeats it. Rotten head trim and stained drywall above window corners are the classic evidence of a missing or backwards one, a detail siding installers and window replacers each assume the other handled.
Where it sits in the glossary
Window head 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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