TL;DR
A base course is the compacted layer of crushed aggregate placed over the subgrade to carry and spread loads under pavers, concrete, or asphalt. For paver patios and walks the standard is 4 to 6 inches of 3/4-inch-minus crushed stone compacted in 2- to 3-inch lifts, deepened to 8 to 12 inches for driveways; the angular fines lock together in a way rounded gravel cannot.
What it means
A base course is the compacted layer of crushed aggregate placed over the subgrade to carry and spread loads under pavers, concrete, or asphalt. For paver patios and walks the standard is 4 to 6 inches of 3/4-inch-minus crushed stone compacted in 2- to 3-inch lifts, deepened to 8 to 12 inches for driveways; the angular fines lock together in a way rounded gravel cannot. Most settlement, rutting, and heaving traces back to this layer being thin, uncompacted, or poorly drained. The ICPI installation standards make its thickness and compaction the line items to look for in a hardscape bid.
Where it sits in the glossary
Base course 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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