If you go to a home center for sealer for concrete, you will notice there are a lot of different types. It can be some-what confusing. There are two basic categories of sealers for concrete: water-based and solvent-based.

Water-based sealers contain very little or no chemical solvents. Their benefits are low odor, low V.O.C’s (Volatile Organic Compounds that can emit irritating gases or vapors.), environmentally friendly and more user friendly. Their disadvantages are less depth of color, shorter life-span, and increased moisture sensitivity.

Solvent-based sealers have less application issues, better performance for most exterior installations, better performance under heavy traffic. However, they have a strong solvent smell, are very flammable, and require special equipment and techniques to be applied.

Within these categories there are two types for sealers: film forming and non-film forming. Examples of film forming sealers are ones that contain acrylics, polyurethanes, epoxies, or polyureas. Non-film forming sealers are water repellants, densifiers, or hardeners). The following are specific types of sealers:

Acrylics: Acrylic sealers can be added with solvents making them the most used concrete sealer for decorative concrete. They provided medium protection and resistance to traffic and chemicals. They can be used on stamped concrete and polymer overlays.

Epoxies: Epoxies are not easy to apply. They offer greater depth of color and protection from chemical spills, abrasion and impact. Over the years they tend to yellow, but with the latest advances in epoxy technology they are able to better resist yellowing from U.V. exposure.

Polyurethanes: A professional should apply Polyurethanes because they are harder to use than the other types of sealers. They offer much better protection against traffic and chemicals but are moisture sensitive.

Polyureas: Polyureas are the latest technology on concrete sealers. They have no solvents or odors and do not yellow. They wear very well and are chemical resistant. They are installer friendly but are the most expensive sealers on the market.

Siloxane: Siloxane and Silane based sealers offer small molecules for penetration into the most  dense stone, brick, ceramic tile, or concrete surfaces. This is the “no show” waterproofing for the areas that don’t look right with the “candy apple glaze” and a more natural look is needed…the effect is almost imperceptible until wet, and best of all, it is truly long term protection.

Silicates: Sodium and Lithium Silicates do not form a film like the other types of sealers. They react with lime and cement materials in concrete making crystals that seal the pores yet still allow passage of moisture vapors. They also help concrete to harden and densify on the surface. The lack of film makes it easier for them to stain.

Sodium Siliconate: Sodium Siliconate is a densifier impregnator the seals the capillary tubes of the slab and forms a layer of hardened concrete to a depth of 1/8-3/8” penetration on open textured prep concrete. This layer of densified, hardened concrete is comparable to a granite surface at approximately 10,000 psi. It can then be polished through a series of diamond abrasives steps to create a polished floor that is virtually maintenance free, chewing gum won’t stick to, and liquids can’t penetrate and stain. It is the Superfloor…

Always consult with your CRS professional to determine which sealer is best for your project, because results will vary depending on the type of concrete finish, temperature, humidity, concrete vapor emissions, traffic patterns and end usage of the facility, etc.