What You Should Know About Asphalt Pavement And Sun Damage

Just as the sun's UV rays can do a number on bare, unprotected skin over time, the same can happen to your asphalt parking lot. A few years of unrelenting exposure to UVA and UVB rays can slowly transform your parking lot into a graying, cracked mess. Such advanced aging not only makes your pavement look old before its time, but it also makes surrounding properties look worn and undesirable.

How Sun Exposure Damages Pavement

For countless organisms, the sun represents life and a crucial source of energy. For freshly-laid asphalt, however, the sun might as well be a gradual harbinger of doom. Traditional asphalt is notorious for readily absorbing solar radiation, resulting in surface temperatures that can climb well into the triple digits on a typical summer day. An ordinary patch of asphalt that's exposed to direct sunlight can easily reach surface temperatures of 170 degrees Fahrenheit or more.

Ultraviolet energy given off by the sun can also do a number on asphalt over time. Continuous exposure to UVA and UVB rays can cause the binding agents in asphalt to break down, weakening the asphalt surface over time. As the asphalt gradually loses its binding agents, the underlying aggregate begins to break through the surface, creating the grayish color commonly associated with aging or neglected parking lots.

Combined with the effects of oxidation, both of these factors can make asphalt surfaces look older before their time.

Your Options for Restoration

Fortunately, you don't have to invest in intensive resurfacing just to repair a sun-damaged parking lot. There are plenty of options to choose from when it comes to rejuvenating and protecting your paved surfaces:

  • Sealcoating - This option involves coating the parking lot with an emulsified asphalt solution containing anti-oxidation additives. Sealcoating not only rejuvenates the appearance of old asphalt, but it also provides effective protection against UV damage.
  • Slurry seal - Slurry seal works similarly to sealcoating, except aggregate is also added to the emulsified asphalt solution. The added aggregate fills in the fine lines caused by lost aggregate over time.
  • Microsurfacing - Microsurfacing takes the slurry seal process a step further by including chemical additives that allows the slurry seal to harden without external heat. This allows the treated pavement to harden faster than a standard slurry seal - usually in 1 to 2 hours.
  • Tire Rubber Modified Surface Seal - This method uses asphalt binders mixed with ground tire rubber to restore lost surface oils and prevent loose aggregate from eroding from the asphalt surface.

Sealcoating is usually considered the simplest and most affordable option for restoring asphalt pavement to like-new condition. TRMSS offers excellent results when it comes to preventing sun damage, but special equipment is required for blending the rubber used in the process. This can add considerable time and expense to an otherwise straightforward project.

Preventive Options Against Sun Damage

When it comes to pavement damage due to sun exposure, a few ounces of prevention can be worth several pounds of cure. Here are a few things to keep in mind as you work to prevent sun and oxidation damage to your asphalt parking lot:

  • Choose your asphalt carefully. It's important to choose your asphalt with long-term durability in mind. For instance, using asphalt with dense-graded aggregate may help combat the long-term effects of sun exposure.
  • Consider alternatives to conventional aggregate. Once such alternative is volcanic rock, which offers better resistance against UV rays while offering a dark, rich color that doesn't suffer as badly from color fade.
  • Use sealcoating as a preventive step. Sealcoating doesn't have to be an option just for old, battered pavement. Giving your freshly laid asphalt a preventive coating can give it some added protection against sun exposure.

By shielding your parking lot from the sun's rays using the tips listed above, you may be able to significantly slow down your parking lot's aging process.