TL;DR
Well casing is the steel or PVC pipe lining a drilled water well from above ground down through the unstable upper formations, holding the borehole open and sealing out surface water and shallow contamination. Codes typically require it to stand at least 12 inches above finished grade, higher in flood-prone areas, topped with a vermin-proof sanitary cap, with the annular space outside it grouted.
What it means
Well casing is the steel or PVC pipe lining a drilled water well from above ground down through the unstable upper formations, holding the borehole open and sealing out surface water and shallow contamination. Codes typically require it to stand at least 12 inches above finished grade, higher in flood-prone areas, topped with a vermin-proof sanitary cap, with the annular space outside it grouted. Diameter, commonly 4 to 6 inches residential, fixes what pumps fit for the life of the well, and cutting it below grade to hide it in landscaping is both illegal in most states and a direct contamination path.
Where it sits in the glossary
Well casing 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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