TL;DR
An extension spring is one of the paired coil springs mounted above a garage door's horizontal tracks that stretch as the door closes and contract to help lift it, in contrast to torsion springs that wind on a shaft above the opening. Each spring must run a safety cable through its core so a snapped coil cannot whip across the garage.
What it means
An extension spring is one of the paired coil springs mounted above a garage door's horizontal tracks that stretch as the door closes and contract to help lift it, in contrast to torsion springs that wind on a shaft above the opening. Each spring must run a safety cable through its core so a snapped coil cannot whip across the garage. They are sold by stretch length and pull weight matched to the door, and uneven left-right wear shows up as a crooked, hard-lifting door.
Where it sits in the glossary
Extension spring 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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