TL;DR
A cold joint is the visible seam created when fresh concrete is placed against concrete that has already begun to set, so the two pours never knit together monolithically. It forms when a truck is delayed mid-pour or a slab is intentionally placed in stages without bonding measures, and it becomes a weak plane that invites cracking and water seepage, especially in foundation walls.
What it means
A cold joint is the visible seam created when fresh concrete is placed against concrete that has already begun to set, so the two pours never knit together monolithically. It forms when a truck is delayed mid-pour or a slab is intentionally placed in stages without bonding measures, and it becomes a weak plane that invites cracking and water seepage, especially in foundation walls. Contractors prevent it by scheduling continuous pours or treating planned stops with keyways, dowels, or bonding agents.
Where it sits in the glossary
Cold joint 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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