In an independent study, sealing cracks in pavement (crack sealing) has proven to be the lowest cost pavement preservation treatment available by far. In asphalt pavements, the next lowest cost pavement preservation treatment is a single chip seal which is approximately a whopping 4 times more expensive. Simply stated, a dollar spent crack sealing returns more benefit than a dollar spent with other preservation treatments. If your goal is to preserve your pavement for the longest period at the lowest cost you must crack seal.
Approximately 75% of cracks in asphalt pavement form into potholes within 3 years if they are not sealed. In drastic comparison, only approximately 1% of cracks that have been sealed will form into potholes within 3 years.
Cracks are inevitable and are going to develop as the asphalt pavement continues to oxidize and deteriorate. However, crack sealing has been proven in studies to slow the rate of cracking. In one study, after 2 years of observation, 75% less cracking was observed in a pavement that was crack sealed in comparison to a pavement that received no treatment at all. Crack sealing can slow the rate of their formation in pavements over time.
Crack sealing as a pretreatment improves the effectiveness of other surface treatments in asphalt pavements. For example, a study showed that when crack sealing was completed as a pre-treatment to a chip seal, 100% less cracking developed after 2 years of observation in comparison to a chip seal only treatment. The chip seal only treatment had already deteriorated back to be equivalent to the “control” pavement that had no treatment completed at all.
In another example, crack sealing plus microsurfacing resulted in 60% less cracking vs. no treatment at year two. Microsurfacing alone resulted in only 15% less cracking vs. no treatment at year two. Again, crack sealing as a pretreatment improves other surface treatments.
If you want to get the most service life from your pavement, crack seal early and often!
- Pavement cracking is inevitable – it is going to happen
- Sealing cracks quickly after they develop reduces the damage to the pavement
- The longer the cracks remains sealed, the longer the pavement will perform
- Visually inspect pavements every year to identify and seal new cracks. Cracks greater than 1/8” (3 mm) must be sealed to achieve the best protection of the pavement.
- Visually inspect previously sealed cracks every year to identify failures and repair as needed. If annual inspection is not possible, previously sealed cracks should be assessed every 3 years, the time it potentially takes for a crack to turn into a pothole.
What is the difference between Crack Sealing & Crack Filling?
It is important to understand that crack sealing and crack filling are different – there are different goals and different materials used.
Crack sealing uses specialized materials that bond to the walls of the crack, while being able to move with the pavement as it expands and contracts, preventing intrusion of water and debris into the crack. Crack sealant is specifically engineered to remain flexible at low temperatures so it doesn’t crack or split open, and remains stable at higher temperatures so that it doesn’t track or bleed on the pavement.
Crack filling uses ordinary materials that do not bond well to the crack; it only fills the void and reduces intrusion of water and debris into the crack and does not move with the pavement as it expands and contracts. Crack filler does not have high or low temperature properties. When pavement movement takes place due to temperature change or traffic loads, the crack filler is separated from the edge allowing water and incompressible materials to enter the crack and into the pavement. Crack filler does not achieve the same level of service life as crack sealant, and it does not preserve the pavement as long as crack sealant. Crack sealing is a long-term pavement preservation solution while crack filling is a band-aid.
Asphalt pavement is referred to as a flexible pavement because it moves horizontally due to changes in temperature and it moves vertically due to traffic loads. Some cracks can open up to 100% of original width as the pavement temperature changes from summer to winter extremes. Generally, asphalt pavement is always moving to some degree and therefore sealing is preferred over filling so that you can truly preserve the gigantic investment in our roads.
What type of solution do you need for your crack sealing project?
There are a variety of crack sealing solutions, and categorizing them can be challenging. Generally there is hot-applied asphaltic-based crack sealant and cold-applied crack sealant. Cold-applied crack sealant should not be confused with cold-applied silicone joint sealant because cracks and joints are different as noted above.
Crafco focuses on quality and long-term performance and therefore manufactures products that have a significant service life like hot-applied asphaltic-based crack sealant and cold-applied silicone joint sealant that have demonstrated in independent studies to provide the longest service life available.