Types of Sealants for Asphalt Driveways

Protecting the integrity of an asphalt driveway is a project that pays off over time and is well worth the investment

By Vickie Ferguson

Photo by istockphoto.com

Asphalt driveways exposed to the sun, rain, snow and standing water are prone to deterioration that cause cracks, crevices and holes that eventually cause the asphalt to crumble. Using a sealant specifically designed for asphalt protects the material while enhancing durability and longevity.

Acrylic

A high-end sealant using acrylics and polymers is the most expensive choice but lasts longer than coal tar or regular asphalt-based sealants. This type of sealant is durable and is unaffected by ultraviolet rays and weather conditions. An application of an acrylic sealant lasts from five to six years, making it cost-effective over a less-expensive sealant. It eliminates the cost of repair to damaged driveways after one to three years from using an inexpensive sealer.

Coal Tar

A coal tar mixture is the second-best sealant for asphalt. Unlike a regular asphalt covering, coal tar is not adversely affected by the sun's ultraviolet rays that promote dryness and cracking of the asphalt material. Coal tar does not absorb liquids and decreases the damage caused by liquids that leak from a vehicle directly onto the driveway. Coal tar sealants are more expensive than regular asphalt coatings and less expensive than acrylic varieties. The price range of coal tar sealants depends on the number of additional additives used in the process when making the sealant to enhance performance, effectiveness and ease of use. A coating of coal tar lasts approximately three to four years between applications.

Asphalt-Based

The least expensive sealant is a mixture equivalent to the asphalt material already in place for the driveway. A thin coating of asphalt over the existing driveway is a short-term solution as the coating will degrade over time the same as the driveway underneath. An asphalt coating does not provide additional protection. Visually, the driveway looks better, but it is still susceptible to the same damaging outdoor conditions. Asphalt sealants cover a larger area because they do not contain the upgraded additives the mid- and higher-grade sealants contain, making them less expensive to manufacture. Coatings average between one to three years before needing a reapplication. The driveway may need additional repair to fill in cracks or replace sections that are damaged or have broken off, due to deterioration prior to applying a sealant.