Crack sealing smooths the way

By Jeff Winke

Procrastination may be the biggest foe a contractor wrestles with when looking at pavement cracks that need to be fixed.

Cracks come in all shapes and sizes. Sealing them in a timely manner is one of the most effective ways to maintain the quality of your pavement. One of the biggest mistakes is waiting too long to begin maintenance.

“Crack sealing is a maintenance practice used to repair cracks and prevent the development of new cracks in asphalt pavement,” states Jenn Brasher, equipment sales and marketing manager for Marathon Equipment Inc., Burlington, Ontario, Canada. “The process involves filling or sealing cracks with rubberized asphalt sealant, to prevent debris or water from infiltrating the pavement. Regular maintenance helps to extend the life of the pavement and prevent future damage of the area. Crack sealing maintenance is important because it can help prevent cracks from turning into more extensive damage, such as potholes.”

Potholes are bad news. They can cause real damage–puncture tires, bend rims and throw steering out of alignment.

“Crack sealing is the absolutely best preventative maintenance item that you can do to prevent potholes from forming,” stated Jason Stepp, vice president, national sales manager with Stepp Manufacturing Co., Inc., North Branch, Minnesota. “Pavement preservation is key. Moisture infiltration is the number one cause for pavement degradation and sealing them with a quality crack sealant prolongs the life by many additional years of service. The key is to get on the problem when the road surface is fairly new and seal the new cracks and come back to them every couple of years to seal the new forming cracks. A little bit of very low-cost preventive maintenance saves high repaving cost in the future.”

Prepping the affected area before crack sealing ensures good results.

“In all cases organics, such as grass and weeds, and sand and dirt must be removed from both the surface and the crack completely, stated Ben Thielbar, director of sales with Cimline, Inc., Plymouth, Minnesota. “For good results, you’ll want to use mechanicals tools and a blower. For better results, you’ll want to use mechanicals tools and an air compressor with greater than 80 CFM and 125 PSI air. And for the best results, you’ll want to include a heat lance to ensure all organics and moisture are out of the crack to promote optimal adhesion. As with all the processes, routing a crack will also improve life cycle and success as it ensures a proper reservoir for material to expand and contract with the crack under changing weather conditions.”

Proper preparation of the affected area requires some thoroughness.

“Best practices are integral to the success of a crack sealing program,” stated Bryan Darling, western regional sales manager, Crafco, Inc., Chandler, Arizona “Crack sealant material has come a long way from the ‘tar’ that was used many years ago. The industry has advanced to the point that the materials used today are highly engineered to properly accommodate the various climates, pavement types, traffic loading, desired longevity, and budget. For example, our product line includes over 100 different specifications of sealants to meet the needs of pavement owners all over the world. All construction specifications and owners’ requirements should first and foremost recognize the importance of demanding the sealant manufacturer’s Installation Instructions to be closely followed.”

Tom Pfuelb, eastern regional sales manager with Crafco, Inc., further explained with prep recommendations:

“Key components to crack sealant performance include:

  • Clean Pavement- crack faces and pavement surface must be free from all dirt, dust, debris and laitance. This can be accomplished by means of compressed air with a minimum 100cfm at 90 psi. Backpack or wheeled blowers cannot adequately clean most pavements. A dirty crack will negatively affect the adhesion of the sealant.
  • Dry Pavement- Crack sealing operations should not be performed when pavements are wet. Hot air lances can be used to remove light surface moisture but should not be used to attempt to dry moisture-laden pavement. Wet crack and pavement surfaces will prevent sealant adhering.
  • Structurally Sound Pavement.
  • Proper Temperatures – you want ambient at a minimum of 50F and a surface temperature at a minimum of 50F.
  • Routing – under the right circumstances, routing can significantly increase sealant performance and longevity. Routing creates a uniform reservoir into which sealant is placed. The routed reservoir has clean vertical sidewalls which enhance adhesion, and the configuration provides for reduced stress on the sealant thereby decreasing the occurrence of adhesive or cohesive failure.”

There are quite a few crack sealants to choose from.

“There are many crack sealer materials available on the market and most are made specifically for the climate in which they are used,” stated Brian Horner, director of sales with ED Etnyre & Co., Oregon, Illinois. “The best results to ensure the crack sealant stays in the cracks is to make sure the cracks are clean and dry before sealant is put into place. Some cracks may require routing to enlarge the crack opening and remove any broken edges. For the best results the cracks should be blown out with high pressure and in some cases a heat lance should be used.”

Horner added, “Most cracks ¼- to 1.5-inches wide or deep can be treated with good success with a traditional wand and crack sealer. For cracks that are smaller other treatments maybe more cost and time effective, like scrub seal or traditional chip seal. If cracks are larger than 1.5- to 2-inches you may consider a mastic product over a traditional crack sealant.”

Cracks can come in all sizes, shapes, and depths.

“The choice of sealant and repair method depends on the type and severity of the crack,” Brasher said. “Transverse cracks are perpendicular to the direction of the pavement and are typically caused by temperature fluctuations. Longitudinal cracks run parallel to the direction of the pavement and are often caused by improper joint construction or shrinkage of the asphalt layer. Hot-pour sealants are commonly used for transverse and longitudinal cracks, to create an adhesive bond against the intrusion of water and foreign materials.”

Brasher continued, “Alligator cracking resembles the pattern of an alligator’s skin and are a sign of serious pavement distress. Mastic is an economical and versatile, permanent repair solution for wide thermal cracks, fatigue cracking, rutting and depressed broken-up areas. It is also recommended for use around solid structures in flexible pavements like manholes, gutters, and drains.”

Crack sealing is an essential practice for preserving the integrity and safety of asphalt pavement. It prevents water from infiltrating the pavement structure, which can cause damage. By sealing cracks early, it can extend the life of the pavement, delaying the need for more costly repairs in the future.

“Every dollar spent on pavement maintenance yields $8 saved in rehabilitation / replacement cost,” Thielbar said. “Crack sealing is the most cost-effective form of pavement maintenance. Customers, whether commercial or agency governmental, should crack seal new pavements and not wait until cracking is overburdened. All cracks not sealed prior to overlay will reflect back through the new surface. Water intrusion begins through the cracks and creates potholes as the water permeates the base where the ground becomes soft causing the asphalt to flex under traffic load and break apart. Protect your investment.”

Brasher concluded, “Crack sealing is a relatively quick process that minimizes disruption to traffic, and creates a smoother, safer driving surface, reducing the risk of accidents and providing better traction for vehicles. For property owners, having well-maintained pavements free of cracks and potholes, can enhance the value of their properties. It is important to always perform a routine checkup and maintenance to save on future repair costs.”