TL;DR
Copper Type K is the heaviest-wall grade of copper water tube, identified by green printing, and the standard choice for underground water service lines between the meter or well and the house. Its thick wall tolerates burial, soil stress, and decades of pressure without the thinner grades' vulnerability, and many utilities and plumbing codes specifically require it from main to meter.
What it means
Copper Type K is the heaviest-wall grade of copper water tube, identified by green printing, and the standard choice for underground water service lines between the meter or well and the house. Its thick wall tolerates burial, soil stress, and decades of pressure without the thinner grades' vulnerability, and many utilities and plumbing codes specifically require it from main to meter. It comes in soft coils for trench work, allowing a splice-free run, and in rigid lengths, and it costs the most of the three common wall thicknesses.
Where it sits in the glossary
Copper Type K 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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