Two people took the time to answer my question last month about what product or mix would protect a concrete floor from salt damage. Thank you to The Swimming Man and The Concrete Technologist. Those are the monikers for Greg Smith and Paul J. St. John, respectively.

Greg owns an award-winning design-build firm in Texas that specializes in pools and spas (thus the name Swimming Man). Just looking at his website makes me want to go swimming (even in Chicago).

He considers Foxfire Enterprises Inc.’s P1007 water-based penetrating sealer “amazing” and inventor George Kubala “old school and brilliant.” According to the company’s website, the formula decreases moisture permeability and porosity by fusing with the alkaline in concrete to fill capillary pores, hairline cracks, and voids.

I’m not sure how innovative that is, but it must be effective against the huge volumes of chlorine (which, after all, has salt in it) and other caustic chemicals Greg's pool and spa projects are submerged in.

Paul, on the other hand, provided a formula of his own: a concrete mix made with at least 35% Class F fly ash and 6% microsilica or equivalent (rice hull ash, ground-granulated blast-furnace slag (GGBFS), metakaolin, diatomaceous earth, or natural pozzolan).

“If you’re concerned about cracking,” he adds, “use Krystol Internal Membrane. After curing is complete (but at least 14 days), apply two coats of alcohol-based silane sealer.”

Thank you, Greg and Paul, for taking the time to comment.

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