Cure your asphalt frustrations with this handy guide
Asphalt takes 24 to 72 hours to dry.
Asphalt usually fully cures after six months to a year.
Asphalt dries and cures fastest in warm, dry, and sunny weather.
When investing in a new surface, the last thing you want is to accidentally damage it by not allowing it to fully dry and cure. Asphalt curing and drying are two distinct processes, both of which play a critical role in how long the asphalt lasts. Use this guide to learn all about asphalt drying and curing times based on factors like weather conditions, asphalt thickness, and air quality.
Curing and drying refer to two distinct phases of the asphalt setting process. Drying is the first phase, which is when the water in the asphalt fully evaporates and leaves the surface dry to the touch. Once the asphalt is dry, it’s firm enough to bear weight, but you still need to take precautions when using it until it’s fully cured.
The curing phase happens after drying. It’s a longer process during which the asphalt continues to harden and gain strength over time. During this process, the asphalt binder, which is typically petroleum based, reacts with the asphalt’s aggregate materials to form a durable structure.
Asphalt typically takes 24 to 72 hours to dry after it’s applied, but the drying time can vary depending on the weather conditions, how thick the asphalt is, and the type of mix used. Most asphalt mixes will provide recommended drying times from the manufacturer. Once it’s dry (but not cured) the asphalt can endure light foot and vehicle traffic without damage.
Asphalt curing can take anywhere from six to 12 months, depending on the specific asphalt mix and the weather conditions. During this period, the asphalt is vulnerable to damage from very heavy loads and sharp objects. It’s not until the asphalt is fully cured that it can reach its full durability and resist those stressors.
Several factors can affect both asphalt curing and drying time, including weather conditions, air quality, and asphalt mix and thickness.
The weather is the most significant factor affecting curing and drying times. Asphalt dries and cures fastest during warm, sunny conditions, which accelerate the evaporation of moisture as well as the chemical reactions needed to cure the asphalt. Wind can also help the asphalt dry faster by blowing off moisture.
When the weather is cold, rainy, snowy, or very humid, it can delay the drying process as it increases moisture and takes longer for it to evaporate. These conditions also make the asphalt slower to cure as they delay the chemical reactions needed to fully harden it.
Asphalt can come in a variety of mixes, which vary by the type and grade of binder used, as well as aggregate size and distribution. Genuinely, dense-graded asphalt with a high number of fine aggregates takes longer to cure than less dense asphalt with fewer and larger aggregates. Consult the manufacturer of your asphalt mix for recommended drying and curing times.
The asphalt’s thickness can also affect drying times. Basically, the thicker the asphalt layer, the longer it takes to dry and cure since heat and moisture must travel a greater distance to escape from the asphalt’s interior to the surface.
Poor air quality and a lack of oxygen content in the atmosphere can delay asphalt curing times since it slows down the oxidation process of the binder needed for the asphalt to fully cure. Additionally, higher altitudes usually have lower air pressure and cooler temperatures, which can delay the evaporation of moisture from the asphalt, increasing drying time.
If your asphalt is dry but not yet cured, you’ll want to take some precautions to preserve its appearance until it fully hardens. The following maintenance tips can keep your asphalt in great condition during this critical period.
Don’t use the new asphalt surface until it’s completely dry, which can take anywhere from 24 to 72 hours.
Avoid using sharp objects or heavy equipment on the asphalt until it’s cured otherwise you can dent the surface.
Regularly inspect your new surface for any signs of distress, like cracks and potholes, and repair the asphalt quickly to prevent further issues. If you’re not comfortable with repairs, you can always hire an asphalt pro to address them for you.
Be careful with petroleum-based products, like oil and gas, which can dissolve the asphalt binder and weaken the surface if spilled.
Promptly remove any vegetation that might sprout through the asphalt, like weeds, to prevent cracks and other damage.
Avoid making very sharp turns or sudden stops with your car since it can scuff the asphalt’s surface before it’s fully hardened.
Ensure that water is draining away from the asphalt since standing water can weaken the surface and lead to damage, particularly during the early stages of curing.
When asphalt cures, it typically changes from a very dark black hue to a lighter, more matte gray color. Cured asphalt also won’t be tacky or sticky to the touch or emit any odors from the asphalt mix. Additionally, fully cured asphalt won’t deform under any pressure.
Yes, you can seal asphalt before it’s fully cured but you should wait to do so until at least three months after installing it. Otherwise, the seal coat can trap the asphalt’s oils and chemicals, preventing it from fully hardening. This can lead to a weaker surface that’s vulnerable to damage. But if you wait at least three months, applying a seal coat can extend its life by protecting it from water, UV rays, and other damaging elements.
Asphalt typically dries and cures best between 50 and 85 degrees Fahrenheit. This range allows moisture to evaporate quickly without causing the asphalt to cool too fast, which can negatively affect the drying process. However, keep in mind that other weather conditions can also affect curing and drying times, such as precipitation and humidity.