UFC 3-270-02
15 March 2001
CHAPTER 3
WHEN TO SEAL
3.1. Field Evaluation. Field evaluations should be conducted a minimum of twice a year, once
during the summer months and once during the winter months. Seasonal evaluations will enable
the determination of the number and size of cracks and will allow performance evaluations of any
existing sealant when the cracks are at their smallest and largest width. Initial sealing should be
considered after cracks have become approximately 1/4 inch (6 millimeters) wide. Cracks less
than 1/4 inch (6 millimeters) wide should not be sealed unless they cover approximately
80 percent or more of the pavement. Pavements that have 80 percent or more of the area
covered by cracks that are 1/4 inch (6 millimeters) wide or smaller should be sealed using some
type of surface treatment (such as a slurry seal), an overlay, or a pavement recycling method.
3.2. Schedule. Crack sealing should be planned and scheduled as determined by field
evaluations. Spot repairs should be made to sealed cracks where the sealant material has failed.
Figures 3.1. and 3.2. show typical areas in need of sealing. Major resealing projects should be
considered for areas where more than 85 percent of the sealant has failed.
3.3. Climate Conditions. Crack sealing projects should be scheduled during the normal
construction season. A normally low rainfall period in the spring or fall is preferred. The
temperature of the pavement should be 50 degrees Fahrenheit (10 degrees Celsius) and rising,
and the crack should be free of moisture and debris before sealing is allowed.
(PFS) are different from a normal asphalt surface. Guidelines provided in paragraph 8.2.,
AFC 3-270-01, "Asphalt Maintenance and Repair," should be used for sealing cracks in a PFS.
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