TL;DR
A subbase is the layer of compacted crushed aggregate placed between the native subgrade and a slab, paver bedding, or asphalt course, distributing loads and providing drainage beneath the pavement. Typical residential sections use 4 to 8 inches of 3/4-inch minus crushed stone compacted in lifts, with driveways and vehicle areas at the thicker end.
What it means
A subbase is the layer of compacted crushed aggregate placed between the native subgrade and a slab, paver bedding, or asphalt course, distributing loads and providing drainage beneath the pavement. Typical residential sections use 4 to 8 inches of 3/4-inch minus crushed stone compacted in lifts, with driveways and vehicle areas at the thicker end. Most flatwork failures, including settling, cracking, and heaving, trace to a subbase that was too thin, poorly compacted, or placed on soft ground, which is why its thickness belongs in the written bid.
Where it sits in the glossary
Subbase 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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