TL;DR
A rebar chair is the small plastic or wire support that holds reinforcing steel at its specified height inside the form before and during a concrete pour, so the bars end up surrounded by the cover the design requires. Heights are sized to put steel at mid-slab or to maintain clearances such as 3 inches against earth.
What it means
A rebar chair is the small plastic or wire support that holds reinforcing steel at its specified height inside the form before and during a concrete pour, so the bars end up surrounded by the cover the design requires. Heights are sized to put steel at mid-slab or to maintain clearances such as 3 inches against earth. Without chairs the mat gets walked to the bottom during placement, where it adds little strength and corrodes—pulling bars up by hand mid-pour never restores accuracy.
Where it sits in the glossary
Rebar chair is part of the Certifications 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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