There is no such thing as an oil repellent concrete sealer. We are here to put an end to the rumor that concrete sealers can stop oil from staining concrete surfaces. The only thing that can stop oil from staining concrete is a coating. Here’s why:
- Water Repellent Sealers: Water repellent sealers, like siliconate sealers and silane siloxane sealers, are the best type of penetrating sealer you can use on concrete. They reduce the absorption of water on the surface, and reduce deterioration caused by water absorption. There are several companies online that push water repellent sealers as oil repellents, but from a chemical perspective, it’s impossible. Water repellent sealers repel water, but they allow for oil to penetrate through. That’s why you can put an oil based sealer or oil based acrylic over a water repellent sealer. Water repellent sealers only stop water. Some companies add fluorocarbons to their formulas but fluorocarbons are not only bad for the environment, but have been proven ineffective when it comes to stopping oil stains. It is important to remember that penetrating sealers work below the surface in the pores of the concrete. The surface of the concrete is exposed. When oil is spilled onto the concrete surface, the oil hits the exposed concrete and a stain is formed. You can put one hundred additives into a penetrating sealer, but all of those additives are carried into the pores with the sealer and the surface of the concrete will always be left exposed.
- Silicate Concrete Sealers: Silicate sealers don’t repel anything, they have no repellency benefits. They reduce the size of the pores by creating a crystalline barrier in them. Regardless of what gets spilled onto the surface, it will all get absorbed into the concrete.
Can sealers help to reduce oil stains? Sealers can’t reduce oil stains, but they can in some cases slow down the movement of oil through the pores of the concrete. Most sealers can’t slow down the absorption of oil for more than a couple of minutes, and in some cases, the oil will cause the sealer to deteriorate as it moves through the pores.
What type of products can stop oil stains? The only types of products that can stop oil stains are concrete coatings. The three most common types of coatings are acrylic sealers, epoxy coatings, and urethane coatings. Acrylic sealers are commonly used on interior and exterior surfaces, while epoxy and urethane coatings are used on indoor applications only.
- Acrylic Sealers: Acrylic sealers are thin coatings that enhance and protect concrete surfaces. They are best known as wet look sealers, but also come in high gloss finishes. Acrylic sealers will protect oil from getting to concrete, but if the oil is left on the acrylic sealer for an extended period of time, the oil will cause the acrylic sealer to soften and the acrylic sealer will have to be repaired.
- Epoxy Coatings: Epoxy coatings are a step up from acrylic sealers, but a step below urethane coatings when it comes to resistance to oil. Oil spills should be cleaned up as soon as possible because leaving oil on an epoxy coating for an extended period of time can cause the epoxy coating to break down or stain.
- Urethane Coatings: Urethane coatings, aliphatic urethane coatings specifically, are the most resistant to oil. It isn’t to say that oil can’t stain an aliphatic urethane coating if left on the surface for an extended period of time, but they offer the most resistance out of any other type of coating.
How To Remove Oil Stains from Concrete
There are a few ways in which you can remove oil stains from concrete. The video below goes over a few common cleaning methods and demonstrates which ones work and which ones don’t. If you prefer chemical removal, you can purchase products like Oil Lift, or other concrete cleaners found at a local hardware store.