Asphalt Paving vs. Asphalt Sealcoating: What are the Differences?

Asphalt paving and asphalt sealcoating are two distinct processes relating to asphalt surfaces such as driveways, parking lots, and roads. If you’re confused about the difference between paving and sealing, pretend you’re spending a day at the beach. To prevent sunburn, you’d apply a protective layer of sunscreen to your skin. 

Driveways and parking lots are similar. Asphalt is the physical structure (in our analogy, the skin) and sealcoating is the protective layer that is applied to the surface. Like sunscreen, it prevents harm from the sun’s ultraviolet rays, as well as damage from other environmental factors like moisture, automotive fluids, and oxidation. 

What is Asphalt Paving?

Asphalt paving involves the initial installation or construction of a new asphalt surface, or the resurfacing of an existing asphalt surface when repairs are required. Asphalt pavement is durable, generally lasting between 15 and 20 years, but over time, factors such as weather and repeated heavy use eventually take their toll, causing the pavement and foundation to deteriorate. Once cracks and potholes form, it’s easier for moisture to seep inside and cause further damage. 

Asphalt paving is typically performed on a bare or prepared surface and may involve an entire driveway or parking lot, or a smaller section of parking lot or road if deterioration is confined to an isolated area. During the paving process, a mixture of asphalt binder (bitumen) and aggregate materials (such as crushed stone, gravel, and sand) is laid and compacted to create a smooth and durable surface. Asphalt paving requires multiple steps including site preparation, grading, application of a base layer followed by the asphalt mixture, and compaction

6 Signs Your Asphalt Needs Paving

Common signs that your driveway or parking lot is in need of asphalt paving include:

  • Extensive Cracks. If your asphalt surface has numerous and significant cracks that cover a large area, it may be an indication that the structural integrity of the pavement has been compromised. Cracks allow water to penetrate the asphalt layers, leading to further deterioration. If the cracks are extensive and cannot be effectively repaired with crack sealing, it may be time for asphalt paving.
  • Potholes. Potholes are deep, bowl-shaped depressions in the asphalt surface caused by the deterioration of the underlying layers. Potholes can pose a safety hazard to vehicles and pedestrians. If your pavement has multiple or large potholes, it is a strong indication that it requires asphalt paving.
  • Alligator Cracking. Alligator cracking is a pattern of interconnected cracks that resemble the scales of an alligator’s skin. It typically indicates a severe structural problem, often caused by a combination of heavy traffic, poor drainage, and aging. If you notice extensive alligator cracking on your driveway or parking lot, it may require new asphalt paving.
  • Sunken or Uneven Areas. Over time, asphalt surfaces can develop low-lying areas or sunken sections. This may result from poor compaction during initial installation, soil erosion, or the weakening of the underlying base layers. Sunken or uneven areas can lead to poor drainage, pooling of water, and further damage to the pavement. If you have significant and widespread sunken or uneven areas, it may be necessary to repave the surface.
  • Widespread Fading and Oxidation. Fading and oxidation are natural processes that occur as asphalt is exposed to sunlight, air, and other environmental factors over time. However, excessive fading and a grayish appearance can indicate the asphalt binder has deteriorated significantly. If the surface looks dull, brittle, and worn out, it may be time to consider asphalt paving to restore its strength and appearance.
  • Age and Lack of Maintenance. Asphalt surfaces have a limited lifespan, typically ranging from 15 to 20 years with proper maintenance. If your asphalt pavement is nearing the end of its expected lifespan or has not received regular maintenance over the years, it may be necessary to consider repaving to ensure a safe and functional surface

What is Asphalt Sealcoating?

Asphalt sealcoating, sometimes referred to as sealing, is a maintenance procedure performed on existing asphalt surfaces to extend their lifespan and protect them from damage caused by environmental factors, automotive fluids, and normal wear and tear. It’s a preventive measure that can extend the life expectancy of asphalt pavement significantly.

During the asphalt sealcoating process, a protective coating or sealant — usually a bitumen- or acrylic-based liquid that contains water, silica sand, polymer additives, and additional fillers — is applied to the surface of the asphalt. In addition to adding a smooth dark finish and making the pavement look more even, the sealant provides a protective barrier against UV rays, moisture penetration, and other elements. It also enhances the curb appeal of your home or business, which can help when it comes time to put your house on the market or attract new customers. 

Asphalt sealcoating is typically performed after the asphalt surface has aged for some time, usually a few months to a year, allowing it to cure and harden. The process includes cleaning the surface, repairing any significant cracks or potholes, applying the sealant with specialized equipment (such as spray systems or squeegees), and letting it cure. Additional layers of asphalt sealcoating are recommended every 2-3 years depending on overall wear and tear.

6 Signs Your Asphalt Needs Sealcoating

Look for the following signs that your pavement could benefit from asphalt sealcoating:

  • Fading and Color Change. If your asphalt surface has started to fade and lose its original black color, it indicates the asphalt binder is degrading due to exposure to sunlight and other environmental factors. Sealcoating can restore the rich, dark color of the asphalt.
  • Surface Cracks. Over time, small cracks can develop on the surface of the asphalt due to temperature changes, aging, and heavy traffic. Numerous or widening surface cracks are a sign that the asphalt is vulnerable to water penetration. Sealcoating fills in these cracks, preventing water from seeping into the underlying layers and causing further damage.
  • Potholes and Depressions. Potholes and low-lying areas or depressions in the asphalt surface are signs of structural weakness. Asphalt sealcoating can even out minor depressions and create a smoother, more level surface, reducing the risk of further deterioration.
  • Oxidation and Brittle Appearance. Over time, asphalt surfaces can become oxidized, resulting in a gray, dull, or brittle appearance. Oxidation weakens the surface and makes it more susceptible to cracks and other damage, which will only grow worse over time. Sealcoating provides a protective layer that prevents oxidation and restores the asphalt’s flexibility and durability.
  • Loss of Aggregate. If you notice loose or dislodged aggregate (small stones or sand) on the surface of your pavement, it indicates that the asphalt binder has worn away, leaving the underlying layers exposed. Asphalt sealcoating replenishes the binder and helps hold the aggregate together, enhancing the surface’s strength and appearance.
  • Water Puddles and Drainage Issues. If water tends to pool or form puddles on the surface after it rains the asphalt has probably lost its ability to properly drain water. Sealcoating can improve the pavement’s smoothness and water runoff, reducing the risk of water damage and prolonging the life of the asphalt.

Asphalt paving and sealcoating are complex and involved processes that often require specialized equipment, skilled labor, and careful planning. Contact the professionals at Rock County Sealcoat for a free, no-obligation quote!