Coating asphalt protects it from UV rays. The sun’s rays normally will increase asphalt’s porosity and make it more susceptible to staining and other damage from things like oil and gas spills. By coating it, you help it resist this damage and extend its life. Have a look at Gettysburg Seal Coating Pros for more info on this.
Finally, coated asphalt is much more water resistant than it otherwise would be. This is very important in climates with a cold winter. Uncoated asphalt can absorb water, which will then freeze and cause cracks when winter comes.
Once you’ve decided to sealcoat your driveway or parking lot, you will need to determine whether you want to do the job yourself or hire a service. Doing the job yourself is cheaper but requires some work. Here is a quick overview of what it takes to do it yourself.
First, the pavement will need to be cleaned. This begins with simple sweeping. You will also need to dig any loose asphalt, gravel or other debris out of the surface. Power washing is likely the easiest way to dislodge the particles. You will also need to cut down any weeds that are growing over or through the surface.
If you used a cleaning method other than power washing, you will now need to scrub the surface with a driveway cleaning solution. This will allow the coating to adhere to the asphalt.
If there are any cracks or potholes, you need to fix them before coating the driveway. Narrow cracks can be filled with semi-liquid filler, while larger ones will need asphalt cold patch. Cold patch is a grainy substance sold in cans or bags.
Potholes will need to be prepared before repair. This generally involves smoothing them out and undercutting the edges to provide a good anchor point for the filler material. Filler can be hot or cold. Most hardware-store fillers will work fine for the light load of a residential driveway.
Actually sealing the asphalt is next. Mix the coating according to the instructions on the package. Then apply it with a rented sprayer or use a pole-mounted trowel to spread it evenly over the surface. Make sure you choose a dry day with no rain predicted so that the coating will have a chance to properly cure.