TL;DR
Air entrainment is the deliberate creation of billions of microscopic air bubbles in concrete using an admixture, giving freezing water in the cured slab tiny relief chambers to expand into instead of fracturing the cement paste. It is essential for exterior concrete in freeze-thaw climates, with specs typically calling for 4 to 7 percent air per ASTM C260.
What it means
Air entrainment is the deliberate creation of billions of microscopic air bubbles in concrete using an admixture, giving freezing water in the cured slab tiny relief chambers to expand into instead of fracturing the cement paste. It is essential for exterior concrete in freeze-thaw climates, with specs typically calling for 4 to 7 percent air per ASTM C260. Without it, driveways and walks exposed to deicing salts scale and spall within a few winters. The tradeoff is a slight strength reduction and a finishing caution: hard steel troweling can seal the surface and defeat the system.
Where it sits in the glossary
Air entrainment is part of the Certifications 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.
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ProFix tools that touch this term
See also
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