TL;DR
A pressure-treated post is dimensional lumber—commonly 4x4 or 6x6 southern pine—infused under pressure with copper-based preservatives so it can be buried without rotting or feeding termites. For burial, the tag must show a ground-contact rating such as UC4A or UC4B; lighter above-ground treatment fails quickly in soil.
What it means
A pressure-treated post is dimensional lumber—commonly 4x4 or 6x6 southern pine—infused under pressure with copper-based preservatives so it can be buried without rotting or feeding termites. For burial, the tag must show a ground-contact rating such as UC4A or UC4B; lighter above-ground treatment fails quickly in soil. Fasteners and hardware touching the wood must be hot-dip galvanized or stainless, because the copper chemistry corrodes ordinary steel.
Where it sits in the glossary
Pressure-treated 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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