A great concrete project will never achieve its full worth without sealers and coatings.
It all comes down which sealer or coating that you choose to apply on the concrete surface. If you want to have the best-looking appearance for your concrete, you might want to consider these options. But if you’ve been using the same sealer on other projects, you’d begin to develop a level of understanding of how it undergoes a reaction with the concrete.
Understanding how concrete sealers and coatings work is tantamount to a better way of working with these materials and a guaranteed success for the project. Here are some of the typical sealers and coatings:
- Solvent based acrylics
- Water based acrylics
- Water based epoxy
- High Solids Epoxies
- Densifiers (penetrating sealers)
But before we get on with explaining each of these, let’s first describe the difference between a sealer and coating. A sealer is basically a product that penetrates a concrete surface to seal it while a coating is a product that remains on top of the concrete creating a layer for visual appeal. Keep in mind that enough coats of a sealer will eventually turn into a coating.
Solvent-based Acrylics – this is by far the most widely-used sealers on the marker today. Because of its easy usage, commendable characteristics and color enhancing abilities, this type of sealer are often found on driveways, pool decks and concrete countertops. Solvent-based acrylics are basically an acrylic emulsion (plastic) dissolved in a solvent often times xylene, acetone or MEK or a combination of both. Once the sealer is applied, the solvent dissipates and leaves behind an acrylic sheet or coating that’s designed to protect the concrete surface from wear and tear as well as enhancing the concrete’s color.
Water-based Acrylics – when you want a sealer that’s not that odorous, has a natural appearance and is environment-friendly, a water-based acrylic is the ultimate answer. Water based acrylics are often white or bluish in color when it is applied but will eventually dry clear. These acrylics are the best alternative indoors where solvents cannot be tolerated that much. Water based acrylics are often reserved for residential use because of its low-build property. They are mostly used for surfaces with an average traffic setting. These systems can leave a natural-looking finish that’s often hard to achieve with high-build coatings.
Water-based Epoxy – these are professional epoxies that come in multi-component kits. This means that the product needs to be mixed before the application. These epoxies are measured with a part A and part B component and blended that creates both a drying and curing effect. Sealers or coatings that cure with chemical reaction are found to be more durable, thicker and more abrasion resistant. They are also known for their good adhesion properties. And if you happen to have a damp surface, some water based epoxies can be applied to it that often creates a cure and seal effect and finish. Water based epoxies makes for a great finish and can also be used as a primary coat which could be where another coat can be applied.
High Solids Epoxies – these epoxies are often associated with coatings. These are mainly designed to add coats and protection to the concrete surface. Epoxies leave a very high percentage of the “plastic” component behind after it is cured, but a high solid epoxy has the exact same thickness when dry as it was wet because evaporation doesn’t occur on any of the solvents. High Solids Epoxies are used as coatings and creates a chemical resistant barrier between the concrete surface and elements. These systems are commonly used in industrial spaces as well as a filler material in Quartz floors, garage floors and epoxy stone systems. The thicker the epoxy is, the stronger and durable the surface is.
Polyurethanes – for high traffic and heavy wear, polyurethanes are the go to sealers. Polyurethanes are known for their excellent resistance to abrasions and its flexibility. Epoxies are always known for their good adhesion. But if you want to have both benefits, an epoxy primer with a bond coat can be combined with a polyurethane top coat. Polyurethanes are available in both water based and solvent based.
Polyurea – these are designed for quick turnaround and industrial use. It’s a quick dry and has excellent adhesion all while maintaining its flexibility, UV stability and chemical resistance. It is quickly being recognized as a good garage floor coating system!
Densifiers (Penetrating Sealers) – these are designed to absorb into the pores of the concrete and seal of the microscopic paths that a liquid could find and ultimately stain the surface. Often times, densifiers are used during the polishing process as a way of hardening the surface of the concrete and making it easier to polish while creating a more functional sealed surface. However, these will not prevent a stain from appearing. It merely lessens and reduces the possibility of these from happening.