TL;DR
A keyway is the groove formed along the top of a concrete footing before it cures, creating a tongue-and-groove interlock when the foundation wall is poured into it, so lateral soil pressure cannot slide the wall off its base. Formed with a beveled 2x4 or stamped channel, it mechanically locks the cold joint that exists wherever wall and footing are placed separately.
What it means
A keyway is the groove formed along the top of a concrete footing before it cures, creating a tongue-and-groove interlock when the foundation wall is poured into it, so lateral soil pressure cannot slide the wall off its base. Formed with a beveled 2x4 or stamped channel, it mechanically locks the cold joint that exists wherever wall and footing are placed separately. Many modern crews substitute vertical rebar dowels, which engineers often prefer, but the groove remains common in residential foundations, and that joint is also a known water path that waterproofing details address.
Where it sits in the glossary
Keyway 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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