What Is The Purpose of Crack Sealing?
Crack sealing or crack filling depending upon how you refer to the procedure is an important step in extending the life of your asphalt. There are two common culprits in developing cracks in the asphalt.
First is base erosion. As the base settles beneath the asphalt surface and loses its integrity, cracks will form in the asphalt. It is important to seal those cracks with an appropriate crack sealant to reduce the negative effects of the cracks. If you do this within the first few years of the asphalt, you can reduce the severity of those cracks. By sealing these cracks, you will divert water to the berm of the asphalt instead of allowing the water to settle in the base which can cause more erosion.
The second harmful component is the Sun. Once a crack develops, the UV from the sun can cause more damage during the expansion of the crack. Crack filling can block out the damaging UV rays that will deteriorate the inside walls of a crack.
SealMaster makes available two types of crack sealants which can be used depending upon the job at hand and what equipment is available.
Cold-Applied Crack Sealants
Cold-applied crack sealants are ideal for repairing asphalt driveways, walking/bicycle pathways, parking lots with light traffic, etc.. Cold-applied crack sealants are available for repairing cracks up to one inch wide.
For cracks up to ½ inch wide, a standard pourable crack sealant works fine. When approaching cracks up to 1 inch wide, it is good idea to upgrade to a trowel grade crack filler. If you know the pavement will see more contracting and expansion than most situations, or is susceptible to heavier traffic, a product offered by SealMaster called FlexMaster would be recommended. If you have what are called alligatored areas or sections with multiple cracks, the recommended material for this application is GatorPave offered by SealMaster which is a product applied by squeegee.
When using cold-applied crack sealants make sure both ambient and surface temperature remains above 50 degrees for a 24-hour period. Also, let the crack sealant dry before opening up to traffic.
Hot-Applied Crack Sealants
Hot-applied crack sealants are available for numerous conditions and can depend upon what type of equipment you have. The two different types of equipment are direct fire machines and oil-jacketed kettles. Be sure to ask your SealMaster representative which hot-pour crack sealant would be recommended with your equipment.
Most hot-applied crack sealants can be used for cracks up to about ¾”. Beyond that, you may have to use the cold-applied trowel grade material. When using hot-pour materials, the minimum ambient and surface temperature must be 40 degrees which gives you a little more of an application window than cold-applied materials.
When using either type of crack sealant, cracks must be free from moisture, dust, and loose aggregate. Some cracks may need to be routed or cleaned out with a wire brush. Also using either type of crack sealant, it is usually a good idea to follow the application with a U-shaped or V-shaped squeegee to help ensure a good seal to prevent moisture from further penetrating the cracks.
Contact SealMaster today with crack sealing questions or any of your pavement maintenance and equipment needs at 800-395-7325. Or, you can e-mail your crack filling concerns to firstname.lastname@example.org