Most cracks are good candidates for filling or sealing. Cracks with widths between 0.2 to 0.75 inches should be sealed. Likewise, cracks showing greater than or equal to 0.1 inch movement should be sealed. Pavements that have failed because of extensive alligator or block cracking may not be candidates for crack sealing methods. In such cases, other methods of repair, such as surface seals or partial depth patching may be more appropriate.
Rubberized asphalts are flexible enough to adjust as cracks open and close.
The final decision about what material to use will depend on the specific properties needed for the intended purpose and on logistical considerations such as preparation time, workability, and cure time. In a 32-month test, SHRP experiments showed that rubberized asphalt and asphalt rubber sealants fail only about 10 percent of the time and silicon sealants fail about 11 percent of the time. Crews should follow several steps when treating cracks. Cold temperatures, dirt, and moisture can prevent proper adhesion between the sides of the crack and the sealing material. Temperatures affect the timing of crack sealing or filling.