Many consumers – and even some professionals – use the terms “sealants” and “sealers” interchangeably, but there is a difference. Sealants are typically rubberized coatings or caulks and create an elastic layer on the surface. Sealers, on the other hand, such as acrylics, urethanes, and epoxies, are either film-forming or penetrating, sealing the substrate internally.
There are dozens of products on the market these days which can cause considerable confusion for consumers looking to preserve and protect their interior and exterior concrete or masonry features. To help clear up matters, let’s take a look at the various major categories of sealing and waterproofing products:
Penetrating sealers include silanes, silosanes, silicates, and siliconates and are used primarily on exterior concrete surfaces subject to corrosion and freeze-thaw damage where a natural, matte finish is desired. Most products provide excellent protection against outdoor exposure conditions and are also breathable, enabling moisture vapor to escape.
Acrylics form a thin protective film on the concrete surface and are available in both solvent- and water-based formulations in a wide range of sheen levels. Acrylics provide good protection against water and chloride intrusion, but usually wear faster than polyurethanes and epoxies. Solvent-based acrylics generally perform better and enhance color better than water-based products for outdoor use.