TL;DR
An inside corner post is the vertical vinyl-siding accessory installed where two walls meet at an interior angle, its channels receiving the siding panel ends from both directions while concealing their cut edges and allowing thermal movement. Crews plumb and fasten it before any panels go on, leaving the prescribed gap at top and bottom and hanging it on slotted nail hems so it can float.
What it means
An inside corner post is the vertical vinyl-siding accessory installed where two walls meet at an interior angle, its channels receiving the siding panel ends from both directions while concealing their cut edges and allowing thermal movement. Crews plumb and fasten it before any panels go on, leaving the prescribed gap at top and bottom and hanging it on slotted nail hems so it can float. The alternative on fiber cement and wood is a square trim board caulked at both shoulders; in vinyl, this molded profile is the standard detail.
Where it sits in the glossary
Inside 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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