Concrete Sealers: Removing Sealers from Concrete

Stripping sealer off concrete is, as Steven Hicks puts it, “nasty.”

It involves strong-smelling, caustic chemicals. It fouls up your equipment. It can burn your skin and pollute your client’s groundwater. “It’s not an easy process,” says Hicks, president of Concrete Science International LLC, a Minnesota concrete contracting firm with franchises across the country. “We avoid it like the plague. You could probably make a living stripping sealer off concrete, but nobody wants to do it.”

It’s not exactly a cash cow either. The going national rate for removing sealer is $1 to $2 per square foot, Hicks says. That’s still only about break-even. “I will not allow any of my company’s locations to do stripping work for under a dollar. You just cannot make money on it.”

But when a contractor is hired to renovate a dingy-looking slab of concrete, removing sealer is often part of the job.

Sealers can be removed with mechanical means such as sandblasting or grinding. But for many contractors, it’s a last resort. It destroys the original surface, exposes the aggregate and is a mess to clean up.

Use the alternative — chemicals — and you can find yourself glove-deep in methylene chloride, which can be so strong that the vapors will burn you simply by creeping between your skin and clothing.