Does your asphalt pavement have excessive cracks or potholes even though it was recently redone?
Houston weather with the excessive summer high temperatures, high amount of rain and year-round humidity take a toll on asphalt parking lots. In addition, leaking fluids from cars in parking lots tend to destroy asphalt as well.
When asphalt is not treated with the proper sealant, oxidation occues and dries out the asphalt binder. When this occurs, the pavement loses flexibility and will start to crack. Oxidation is when the sun’s ultraviolet rays harden and dry out the asphalt surface. This accelerates erosion and reduces asphalt thickness so that in just a few years the pavement needs to be totally resurfaced.
As oxidation occurs, then the rain, chemicals and other pollutants seep into the cracks and the pavement deterioration begins to rapidly progress. Once the process starts, the damage has occurred.
Applying a sealcoat protects the surface of the asphalt and reduces the damaging effects of oxidation and the Houston weather extremes. This application will greatly extend the service life of pavement as well as enhance the overall appearance. Sealcoating keeps and will even restore the original dark color of asphalt to greatly enhance the overall appearance of the property.
If you were to look at a cross section of treated and untreated asphalt, you will see the difference that a sealcoat makes.
In addition to the improved physical appearance, the sealed pavement becomes a smoother surface to make sweeping and maintenance easier and less costly. The most important aspect is the ability of the asphalt pavement to resist the damaging effects of gas, oil and chemical salts.
What does asphalt consist of?
Asphalt pavement is a mixture of crushed stone (known as aggregates) and chemical binders that glue the mixture together. Over time the sun’s ultraviolet rays break down the binding materials allowing moisture to fill in the cracks and subjecting the empty spaces (known as voids) to expand and contract breaking down the integrity of the pavements. This is most noticeable when pavement changes from black to a dull gray. As the process continues, the binding materials continue to weaken until large visible cracks and potholes develop.
What does sealcoating do?
Sealcoating prevents the adhesive qualities of the asphalt binders from being broken down as quickly. The most important benefit is it’s ability to prevent premature pavement wear. Sealcoating is a good investment when applying new asphalt pavement and parking lots or when updating those in need of minor repair.
How is sealcoating applied?
First the pavement surface is swept and all visible potholes or cracks are cleaned and filled. The sealcoat is applied using a sprayer to ensure proper thickness. A high quality sealcoat has the proper ratio of additives and fine sand as an aggregate to make the survey more durable and non-slip. We recommend a second coat on roadways and other high volume traffic areas to ensure longer service life of the pavement.
As we mentioned, it is important to fill cracks to keep them from expanding and causing others to form. We suggest using a rubberized hot crack fill material to provide a flexible that reaches into cracks and crevices. We also recommend that during all pavement repairs that you make sure pedestrians and vehicles are kept away until all materials have had time to completely dry.
You can expect these types of pavement repairs will last for many years of normal use.