TL;DR
An outside corner post is the vertical vinyl or aluminum trim piece that finishes the meeting of two siding walls at an external corner, with channels that receive and conceal the panel ends from both directions. Installed plumb before siding panels go on, it must be hung from the top fastener and allowed to expand, with the bottom lapping any starter or skirt flashing.
What it means
An outside corner post is the vertical vinyl or aluminum trim piece that finishes the meeting of two siding walls at an external corner, with channels that receive and conceal the panel ends from both directions. Installed plumb before siding panels go on, it must be hung from the top fastener and allowed to expand, with the bottom lapping any starter or skirt flashing. Wavy or bowed ones telegraph rushed installation, and color-matched replacements are a routine siding repair.
Where it sits in the glossary
Outside corner post 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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