In the paving industry, there has been a long-term debate regarding the pros and cons of both coal tar and asphalt seal coats. And anyone that works in the industry is either for one way or the other, having a strong opinion and preference about each. Although coal tar was used prior to World War II, asphalt-based seal coats were an innovative and exciting addition to the paving industry in the 1980’s.
Continue reading to learn more about these two types of seal coating materials, as well as, the pros and cons of of each.
Coal Tar Seal Coats
As mentioned, coal tar-based seal coats were used prior to World War II, and have been the customary seal coat for asphalt pavements east of the Rocky Mountains for many years. But in the recent years, many states and municipalities have banned the use and sale of coal tar seal coats for environmental and health reasons. Such states include Washington, Illinois, New York, Minnesota, Maryland, Washington State, The District of Columbia, and Austen Texas. The reason for such bans has to do with coal tar seal coat toxicity. It contains 20 to 30 percent coal tar pitch, which is a steel manufacturing by-product made of 50% polycyclic aromatic hydrocarbons (PAHs), which are harmful to humans and the environment. In fact, it is considered a human carcinogen.
Although there are drawbacks to coal tar emulsions, there are a few strong points worth mentioning as well. Coal tar seal coating is highly durable and the application process is easy. It’s also oil and fuel resistant. It is said that the application of coal tar seal coating has to be precise in order to prevent harming the environment and jeopardizing human health; but everyone has their own opinions about this!
Asphalt Seal Coats
Many in the industry look to asphalt-based seal coats as an alternative to the off-putting coal tar based materials. It is a byproduct of petroleum refining and provides a deep, rich black topcoat color. They are much better for the environment because they do not emit harmful volatile organic compounds (VOC’s). This makes this a great alternative to coal tar emulsions. It is also easy to install and less prone to cracking. A few downfalls to asphalt-based sealcoats include their vulnerability to fuel and oil. Unlike coal tar sealcoats, asphalt-based sealers are less resistant to oil, gasoline, and more.
Indianapolis Commercial Paving and Sealcoating Services
Call ACI Asphalt and Concrete at 317-549-1833 for commercial pavement repair and sealcoating service in Indianapolis, Indiana. Our licensed road construction contractors provide a wide range of asphalt and concrete work for commercial and industrial properties, including inspections, installation, replacement, repair, and more. We also offer free estimates and consultations, flexible scheduling, references upon request, and more. Best of all, our work is backed by our 100% Satisfaction Guarantee, so you can rest assure that your investment is sound. Request a free quote, today.