TL;DR
A dishwasher high loop is the routing of the drain hose up to the underside of the countertop, secured there before it descends to the disposal or sink tailpiece, so dirty sink water cannot flow backward into the machine. The elevated arc acts as a passive backflow barrier; plumbing codes in many jurisdictions accept it, while some, notably in states requiring air gaps, demand the chrome air-gap fitting on the sink deck instead.
What it means
A dishwasher high loop is the routing of the drain hose up to the underside of the countertop, secured there before it descends to the disposal or sink tailpiece, so dirty sink water cannot flow backward into the machine. The elevated arc acts as a passive backflow barrier; plumbing codes in many jurisdictions accept it, while some, notably in states requiring air gaps, demand the chrome air-gap fitting on the sink deck instead. A hose left looping low behind the cabinet is the quiet reason some dishwashers always hold a puddle of gray water.
Where it sits in the glossary
Dishwasher high loop 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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