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Concrete Sealers
Keep your work beautiful by choosing the right sealer for the job
by Susan Brimo-Cox
Because they actually penetrate into the concrete surface — 1⁄8 to 3⁄16 of an inch on average, Churray says — these sealers are particularly effective. Glessner reports silane and siloxane sealers provide very good water resistance, while fluorinated resins are designed to resist oil penetration.
These sealers are expensive but easy to apply. Because they do not change the appearance of the concrete surface, they may be a good choice when a natural appearance is desired. However, in some applications, the lack of sheen can be considered a disadvantage.
Churray points out that these products are often used by state highway departments on bridge surfaces. “Parking garages are another good application.”
Jeffrey Potvin, owner of Architectural Concrete Consultants Inc. of Lutz, Fla., explains some penetrating sealers are used as a “water” blocker with a film-forming sealer applied on top.
“Surface preparation cannot be emphasized enough,” Livingston says. “Proper cleaning, surface pH, surface temperature, surface dryness…. If there is any question about whether a surface has been cleaned properly, clean it again!”
Vollmer emphasizes that it is important to mop several times with clean, clear water. “The No. 1 problem is using water that’s not clean and not cleaning your mop regularly. Then, wait for the floor to dry before sealing.”
 “Over acid stains or over acid cleaners, you need to neutralize the surface before sealing,” says Glessner. “Water-based acrylics are particularly prone to destabilization in contact with acid.” (Neutralize by adding a basic material such as baking soda or ammonia. Flushing with plain water does not neutralize an acid).
Mark Donaldson, director of operations for Skookum Floors USA in Seattle, cautions, “Each system requires different surface preparation, although you will almost always find that the surface must be free from all sealers, waxes, dust contaminates and other potential bond breakers. Some systems require a minimum surface profile, while others require the product to be scrubbed into the surface. Always read the manufacturers’ recommendations for installation.”
Iwaniec agrees. “It is very important to refer to the technical data sheets and material safety data sheets for the product to determine proper application.” Depending on the product, application techniques “can vary between brushing, rolling, lambswool applicators, squeeges/trowels, low pressure pump sprayers and electric airless sprayers.”
Improper application, over-application or applying sealers too thickly can cause problems. Depending on the product used, two thin coats may be better than one heavy coat. Or backrolling or back brushing may be required. Some products are more forgiving than others. Other times you may have to sacrifice ease of application for durability.
“You have to be real careful about over-application,” says Potvin. “There will be a recommended film thickness you need to follow to ensure correct curing.”
Longevity of a sealer usually depends on the wear-and-tear of the surface and the maintenance schedule. One of the biggest problems is maintaining the surfaces properly. Vollmer recommends, “Use the proper chemicals to clean the floors — watch out for ammonia and other harsh chemicals and cleaners. Use cleaners compatible with the [sealer and/or wax] used.”
Potvin says water latents (mineral deposits) can also cause problems — and do at a lot of theme parks — so it’s important to remove puddles and standing water.
Manufacturers and contractors alike recommend routine inspection of the sealed surface. Moisture should not penetrate the surface if it is well-maintained. Similarly, if the pores of the concrete surface are sealed correctly, mold and mildew should not become a problem.
There is a sealer for just about every concrete application — horizontal and vertical, as well as concrete pavers, masonry, stucco, unglazed tile, natural stone, manufactured stone and brick.
However, “there is no one sealer that can be used for all applications,” Livingston points out. He suggests you ask yourself many questions before selecting or specifying a sealer.
For example: Are you concerned about UV resistance? Abrasion resistance? Moisture, stains or chemicals? What are your state and local regulations regarding solvent-based products? Is there vegetation nearby the project that might be damaged by solvent-based products? How long will the sealer last? Does the manufacturer provide a warranty?
Don’t be afraid to ask for help. “Sealers and coatings require an educated experienced installer to successfully select and ultimately install,” explains Donaldson. “It is important to have a close relationship with the manufacturer and have all the required variables brought to the table before selecting and installing a sealer or coating system. As a beginner the easier-to-install systems usually consist of acrylic-based or one-component systems. These are a good stepping stone to eventually move into the multi-component, harder, more chemical- and wear-resistant systems.”
Doug Carlton, owner of Carlton Concrete Co. in Visalia, Calif., says that while sealers can be a difficult area to grasp, it is an area that contractors should thoroughly explore. “I believe a contractor should only seal with products they learn inside and out. Sealer is the Achilles’ heel of decorative concrete. The secret is becoming comfortable with the product you are using.”
Unfortunately, what you may need to know about concrete sealers isn’t necessarily cut-and-dry. Some manufacturers combine technologies for hybrid products; such as blending acrylic and urethane or acrylic and siloxane. In other cases, additives are introduced to help solve some potential problems. For example, fine grit or silica is sometimes incorporated to provide slip resistance.
Some sealers can be used in combination with others for enhanced results; for example, applying urethane over epoxy, or an acrylic sealer over a penetrating sealer. If you layer sealer products, though, be sure to use compatible products.
“In most cases, stick with the same manufacturer,” advises Potvin. “Most contractors aren’t chemists and are looking at dollar signs rather than compatibility. The [compatibility] problems often don’t show up until later.”
In making your final decision about a sealer, remember the sealer is a small part of the overall cost of a project. As Churray points out, “It’s not the place to save pennies. You rely on customer satisfaction and word of mouth that you do quality work.”
Donaldson says, “We like to relate price to cost. A less expensive system initially might add up to a costly mistake down the road. Imagine saving 25 cents a foot initially but having to shut down operations in a year to refinish a worn and damaged sealer system. Explain this to the customer and always offer a couple options for their review.”
“So many people get stuck using one type of product because they don’t know what else is out there,” Iwaniec says. “It is important to try more than one product so you can compare your end results.”
If you can inform your customer about various concrete sealer products, you convey the appearance of someone who is knowledgeable and up-to-date with technological changes in the industry. And some customers are willing to pay more for a knowledgeable contactor and a better product.
After all, making the right sealer choice enhances and prolongs the life of your hard work. Learning about the options out there and getting the support and technical assistance you need from a reputable sealer manufacturer makes good business sense. |
It’s more than a price decision
