Hot crack filler is the preferred method of crack repair in comparison to cold crack fillers. Hot asphalt crack filling, sometimes called hot tar crack filling or sealing, is a generic term that describes a hot melt method to fill asphalt pavement cracks. Although concrete cracks can be filled with this same type of crack filler, it is not desired due to the asphalt rubber’s darker color. Hot crack filler is a rubber containing sealant that should be heated to around 400º with asphalt melting equipment and applied with crack filling machines. Most contractors prefer hot crack filler over cold pour because the hot melt asphalt sealant allows traffic in less than 30 minutes of laying it down, compared to hours with cold.
Hot crack filling on driveways
Generally speaking, a standard driveway uses about 6 blocks. A long driveway or a small parking lot uses about 12 blocks. Hot crack filler is traffic ready as soon as it cools down enough to become not tacky anymore, which takes 10-40 minutes depending on the weather. In cold weather the melted crack filler cools faster. To test, you can use a stick to poke the filler sealant, if it does not tack to the stick then you are ready for foot traffic.
Unlike cold pour crack filler that needs to dry (cure) over a long time, there is no curing for hot asphalt crack fillers. While cold pour crack filler dries in about 24-48 hours, hot pour crack filler is traffic ready in 10-40 minutes, as long as the applied sealant cools down to ambient temperature. Give it an additional ten minutes for vehicle traffic.
Sand
Although applying sand on top of the sealed crack is not required, doing so can increase traction for foot and vehicle traffic. It might be beneficial to apply sand if there will be traffic driving or walking through prior to the crack filler completely drying. It is best to use silica sand since silicon dioxide (silica) is resistant to acid corrosion. On the other hand, regular sand may be acceptable for the short term, though the large amount of impurities in regular sand may affect the sealcoat applied on top of it.
Each pound of hot crack filler covers about 7-8 linear feet of medium width cracks. Each crack filler block covers about 150 linear feet of medium cracks, or 200 linear feet of small cracks. It is recommended that for large and deep pavement cracks, fill the crack with silica sand till about half inch to the pavement surface prior to pouring crack filler product. This gives better structural support as well as using the crack filler more efficiently.
Weather
Weather is a factor in drying, it is recommended to fill cracks when pavement is at least 40°F. That being said it is still possible to fill cracks in cold weather by heating up the pavement by using a heat lance or a weed torch. Torching the cracks prior to crack filling also makes sure the crack walls are completely void of moisture.
Try to keep the crack fill machine’s temperature under 500°F as prolonged exposure to high heat will oxidize and age the asphalt in the crack filler. The best temperature is 380 – 400°F (193 – 204°C).
Durability
Generally speaking, unlike cold crack filler, which is emulsified with water, hot crack filler does not “expire”. Most hot asphalt crack filler has a shelf life of 10 years or more. If stored outside, make sure to keep unboxed sealants out of direct sunlight as UV damage is one major factor that ages the sealant. In addition, prolonged high temperature can accelerate asphalt aging, so when the weather gets hot it may be a good idea to bring the crack filler indoors or to a cool shady place.
Seal coat over the filled cracks
Both hot rubber asphalt crack filler and cold pour crack filler cracks can be sealed over with a driveway sealer. All are asphalt-based products. For liquid cold pour crack filler, it is important to let the sealant dry completely before spraying or squeegeeing on sealcoat, as trapped water will affect bonding later. It takes cold crack filler 24 to 48 hours to completely dry.
For hot pour crack filler, as there is no water in the formula, it is ready for sealcoat application much sooner, usually in 20-40 minutes. It is important to let the hot crack filler cool down to ambient temperature prior to applying driveway sealer.
Hot pour crack filler work with latex paint
Use it with caution. The rubber asphalt will bond to the paint. However, the paint might peel off the pavement over time.
Contact us
Our masonry, concrete, hardscape, and paving experts serve all central and northern New Jersey including Bergen, Essex, Hudson, Hunterdon, Passaic, and Union Counties. We specialize in custom design. Address 55 Terrill Road, Plainfield, NJ 07062. https://junsproservices.com