TL;DR
A water penetration rating is the tested pressure, expressed in pounds per square foot, at which a window or door assembly begins to leak when sprayed with water under static or cyclic wind pressure per ASTM E331 and E547. It rides inside the unit's performance grade: a window labeled PG35 resists water at 15 percent of its design pressure, so higher grades mean tighter units in wind-driven rain.
What it means
A water penetration rating is the tested pressure, expressed in pounds per square foot, at which a window or door assembly begins to leak when sprayed with water under static or cyclic wind pressure per ASTM E331 and E547. It rides inside the unit's performance grade: a window labeled PG35 resists water at 15 percent of its design pressure, so higher grades mean tighter units in wind-driven rain. Coastal and high-rise specifications lean on this number hard, and a unit that meets it in the lab still leaks in the wall if the installation flashing fails, which is where most field water problems actually originate.
Where it sits in the glossary
Water penetration rating 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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