CONCRETE SEALERS - BUYING TIPS(2)

Source:www.stonediamondtool.com Date:2018/10/23 Read:485

Questions to ask before you buy

Contributions by Bob Harris and Chris Sullivan

What Conditions Will the Sealer Be Exposed To?

To keep maintenance to a minimum, it's important to select a sealer that will protect your concrete or decorative overlay from the traffic conditions and elements to which it will be exposed. For example, for a stamped concrete driveway, you'll need a sealer that repels oil and grease stains, prevents penetration of water and deicing chemicals, and resists abrasion.

The primary type of sealer used for exterior concrete flatwork is a solvent- or water-based acrylic. If you don't want a sheen on the surface and prefer a natural look, a penetrating sealer is an alternative that provides excellent protection against outdoor exposure conditions.

For a decorative interior floor, a high-build sealer with good resistance to scuffs and staining, such as a polyurethane or epoxy, will generally provide the best protection and be easier to maintain. On indoor surfaces, softer acrylic sealers usually require regular maintenance with several coats of a sacrificial floor finish, or wax, to prevent wear and black heel marks.

Is the Sealer Breathable?

One of the reasons acrylic sealers are commonly used for exterior applications is because they are "breathable" - they provide good water repellence while allowing moisture vapor within the slab to escape. Most penetrating sealers are also breathable.

Epoxies offer excellent water repellence, but some products are impermeable and can end up trapping moisture in the concrete. If you suspect that excess moisture is present in the slab, whether indoors or out, make sure the sealer you use is permeable and won't restrict the ability of the concrete to release moisture vapor as needed. Read this article by Robert Cain for more information on controlling moisture-vapor transmission.

How Long Will the Concrete Sealer Take to Dry?

How soon a sealer can be recoated or opened to traffic may be critical on fast-track projects. Acrylic sealers dry the fastest, setting to the touch within 30 to 60 minutes after application and ready for light traffic as soon as 12 hours after the final coat, depending on air temperature, humidity levels, and other environmental conditions. Polyurethanes and epoxies typically require longer curing times of at least 24 hours.

Is the Product Safe to Apply Indoors?

When working indoors, it's usually safer to use a water-based rather than solvent-based product, especially if the area can't be ventilated. Solvent-based sealers are extremely flammable and the fumes they emit can be hazardous to breathe.

What Type of Finish and Surface Appearance Do You Want to Achieve?

If you're after a wet look to enhance the appearance of colored finishes, choose a sealer with a medium- to high-gloss sheen. Most acrylic sealers are available in a range of sheen levels. Solvent-based acrylics generally enhance color better than water-based products. For an additional color boost, you can even create color washes with some acrylic sealers by mixing in powdered or liquid tints.

For applications where a shiny or wet look is not desirable, you can also find film-forming sealers with matte or low-gloss finishes. There are even "flattening agents" available that can be mixed into some sealers to control the level of gloss. Another option is to use a penetrating sealer that won't leave a surface film.

In high-traffic areas, the slip resistance of a sealer may also be important. For these surfaces, look for a sealer that exceeds ASTM D2047 slip-resistance requirements.

What Is the Life Expectancy of the Sealer, and Does the Manufacturer Provide a Warranty?

The life expectancy of a sealer depends, in part, on exposure conditions and how well the sealer is maintained. In general, however, epoxies and urethanes deliver the best long-term performance and can last years before the need for reapplication. Some manufacturers may even provide a warranty to back the performance claims for their products. However, this warranty will be null and void if you don't adhere to the manufacturer's guidelines when applying the sealer.

Notice that cost is not one of the key considerations listed here. Certainly, you should compare prices of similar products to get the best value, but don't try to pinch pennies. Sealer is too important to the overall appearance and longevity of your work. Plus, you don't want to give your clients a protective finish that will wear away after only a year or so. "When it comes to sealers, you really do get what you pay for. Save now, pay later is often the result of going cheap," says Sullivan.