Sealcoating: Is thicker better?

When contractors explain the asphalt sealing process, some customers question whether it would be better to apply the sealant in a thicker layer to improve the protection it provides or to shorten the time that the area must be closed to traffic. Although it might seem reasonable to “get it over with” faster by applying a thick coat instead of two thin coats, thicker layers are always a very bad idea.

The problem with thick asphalt seal coats

Sealcoating dries by evaporating the water contained in the mixture. When a thick coat is applied, the water molecules have more difficulty making their way through the sealant and into the air. Drying time is lengthened significantly; in fact, two thin coats often dry much faster than a single thick coat. The thicker coat can remain tacky, allowing it to be tracked inside your building. Furthermore, if sealcoating is applied too thickly, it will likely crack and turn to dust, negating any expected benefits.

What is seal coating supposed to do?

Sealcoating is supposed to dry to a hard film that protects asphalt pavement from damage. This hard film acts as a barrier to prevent automotive fluids, traffic and water from causing the pavement to deteriorate prematurely. If sealcoating is applied too thickly, it will be extremely difficult for this hard barrier to develop. As a result, your pavement will have only limited protection against the elements.

The barrier also makes it easier to remove oil and other automotive fluids that have leaked on your pavement. Petroleum-based products soften asphalt, but if sealcoating is properly applied, the process is slowed substantially. This gives you more time to remove them before they can damage your pavement. However, if the sealcoating is applied so thickly that it does not cure properly, your pavement will have little or no protection against automotive fluids.

Sealcoating also shields your pavement from ultraviolet radiation. The sun’s rays fade the color of asphalt pavement, but they also make it dry and brittle. To provide the best protection against UV rays, however, the sealcoating must cure properly, and this is difficult or impossible if the sealant is applied too thickly.

How to get it right? Hire a trustworthy contractor

If you want your sealcoating applied correctly, you should take the time to locate trustworthy, experienced asphalt companies. Unscrupulous sealcoating contractors may try to apply the sealant in a single heavy pass so that they can perform more jobs in less time. They are interested in making more money with less effort; they are not interested in providing you with quality work or making the best decisions for your specific needs.

Remember, experience counts.

APM is an asphalt company and we have been applying sealants for more than 35 years. Whether we are sealcoating a parking lot or repairing a city street, we take pride in the quality of our work. APM offers an extensive range of services, including sealcoating, parking lot striping, asphalt paving, concrete repairs, curbing, asphalt overlays, pavement reinforcement, asphalt repairs, milling, site work and ADA improvements. We also install bumper blocks, speed bumps, car stops and parking lot signs. Our customers include shopping centers, office parks, municipalities, retail stores, churches, apartment complexes, schools, restaurants and subdivisions. If you would like a free quote, you can either submit the online form or call us at (859) 299-8111.

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