TL;DR
Copper Type L is the medium-wall grade of copper water tube, marked in blue, and the workhorse for interior supply piping where a step up from minimum is wanted. It is approved for both above-grade and buried use, handles aggressive water longer than thinner tube, and is what most plumbers mean when a quote simply says copper repipe.
What it means
Copper Type L is the medium-wall grade of copper water tube, marked in blue, and the workhorse for interior supply piping where a step up from minimum is wanted. It is approved for both above-grade and buried use, handles aggressive water longer than thinner tube, and is what most plumbers mean when a quote simply says copper repipe. Available rigid or in soft coils, it costs more than Type M but less than Type K, a middle position that has made it the default specification in much of the country.
Where it sits in the glossary
Copper Type L 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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