Benefits of Seal Coating
Seal coating is designed to protect asphalt pavements from the damaging effects of the environment, including moisture and ultraviolet oxidation. Protecting pavement with seal coating has basically the same effect as using sunblock on your skin or varnish on wood – it slows the destructive effects of the weather. Seal coating also minimizes raveling (the loss of aggregate) and fills minor voids on the surface. Other benefits include creating a uniform color and appearance for all paved asphalt surfaces and increasing the visibility of curbing. Seal coating and restriping of parking spaces and crosswalks improve traffic flow and enhance public safety.
Frequency of Seal Coating
To reduce long-term maintenance expenses, industry experts recommend that pavement be seal-coated every two to five years, depending on traffic and overall condition. Pavements that exhibit extensive cracking, base failure or severe surface raveling will not significantly benefit from seal coating. Also, seal coat tends not to adhere well to areas saturated with oil, so such areas must be treated with an oil spot primer to aid adhesion. Sealer can be applied by either squeegee or spray methods. The spray method is recommended for smooth pavement, whereas rough, porous surfaces are better serviced by the squeegee method with its thicker application. Normal curing time is 24 hours for moderate temperature and humidity conditions.