TL;DR
A header is the horizontal structural member spanning the top of a door, window, or other wall opening, carrying loads from above down into the trimmer studs at each side. In bearing walls it is sized from span tables or engineering, built from doubled 2x lumber, LVL, or steel; in non-bearing walls a flat 2x4 may suffice.
What it means
A header is the horizontal structural member spanning the top of a door, window, or other wall opening, carrying loads from above down into the trimmer studs at each side. In bearing walls it is sized from span tables or engineering, built from doubled 2x lumber, LVL, or steel; in non-bearing walls a flat 2x4 may suffice. Undersized examples announce themselves with sagging drywall cracks radiating from opening corners and windows that bind, and replacing one requires temporary shoring of the wall above.
Where it sits in the glossary
Header 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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