Photos are of 27,000-square-foot Dueck GM showroom, the third largest in North America.

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Acrylic Stains for Concrete:
A Colorful Alternative to Acid Etch
by Denise Wendt

Combining systems
Acrylic stains can be used on top of acid-etch stains to create a stronger and more authentic look. Anderson, Donaldson and Sullivan agree that when combined correctly and applied artistically, the results can be fantastic. “A wider range of color and effect can be achieved with the combination of systems,” says Anderson. “It is absolutely necessary to use them [together] to achieve exact color matches and unique finishes,” adds Donaldson. “We have seen our top-end applicators create stunning color combinations by blending our Patina acid stains and Cemtint acrylic water-based penetrating stains,” says Sullivan.

Choosing a sealer
All acrylic stains are not the same, and neither are their sealers. Some stains are surface treatments, while others act as a penetrating stain. “A surface stain will wear faster then a penetrating stain in side-by-side wear comparison tests,” says Sullivan. “That said, the sealer system used is intended to take all the wear. Properly maintained, the stain — no matter what type — should never be affected.”

Acrylic stains demand a durable topcoat, and our sources recommended a variety of sealers, depending on the job and desired effect. When UV and wear is an issue, Donaldson uses commercial-grade UV-resistant sealant and coating systems. Anderson recommends matching bases; that is, if your stain is water-based, choose a water-based sealer. “The wear resistance depends on the type and quality of sealer you use, as well as the maintenance program given to the client,” she says.

“Sealer selection is one of the most important factors in stain application, and can also be one of the most confusing,” says Sullivan. “Cutting corners with cheap sealers is the fastest way to fail,” he says. He recommends spending a little more for a high-end sealer designed for high-end stain applications. “High-build sealers such as polyurethanes and epoxies provide the best wear, stain resistance and life span,” says Sullivan. Because most epoxies will yellow over time, he recommends non-yellowing polyurethane sealers, followed by acrylic systems.

Sullivan recommends applying a base coat of medium solids (18 to 27 percent) water- or solvent-based acrylic sealer, followed by two to three coats of a high solids top coat sealer. These top coat sealers — or sacrificial sealers — are growing in popularity and have become a staple for high-end stain applicators. “Top coat sealers provide a durable wear surface that can be easily and inexpensively reapplied without stripping previous coats,” he says. “They also adhere to almost any type of base sealer, from polyurethane to acrylics.”

As with any coloring system, moisture problems in the concrete can negatively affect acrylic stains. Moisture, if it gets trapped under the sealer, can change the appearance of the stain or bring a migration of salts (efflorescence) to the surface. Pressure from underneath can make the stain pop and peel off.

Make maintenance a priority
Maintenance is critical with acrylic-based stains. And the level and type of maintenance required depends on the sealer, coating and finishes used — not the stain underneath. Because the level of penetration is slight to none compared with acid stains, maintaining the sealer system is crucial.
Sullivan urges applicators to produce samples and get them approved prior to application. “Applicators also need to sell prospective clients on the fact that stains are not coatings and will produce random affects. That is the nature and beauty of all concrete stains,” he says.

The picture is a patio stained with H&C Shield Plus Ultra and stenciled using the H&C stencil.

The pros and cons of acrylics
Acrylics offer many advantages over chemical stains: With acrylics, applicators can create colors not obtainable by acid-based stains. When sealed correctly, acrylics can resist wear and exposure well. They typically need less time to react or cure than chemical stains. Because they are water-based, they emit few volatile organic compounds and clean up is easier. In most cases a simple damp mop application is all that is needed before sealing. And depending on the quality of the application technique and the materials used, acrylic stains can be used on almost any surface, including previously painted surfaces and asphalt.

But there are disadvantages to acrylics worth noting. They often require initial surface preparation and acid washing. They aren’t naturally UV stable. And they lack the permanence that acid stains provide. While they offer more color choices than can be obtained with chemical stains, they offer less variation in color. “Nothing can produce the natural variegation effects of acid-based stains,” says Sullivan.

Their ease of use may explain their growing popularity, especially with do-it-yourselfers.

“A lot more things can go wrong in the application process with acid stains if you are not familiar with the product,” Strongosky says. “An acrylic stain is easy for anyone to use.”