Did you know that the most important function for maintaining your asphalt driveway or parking area is to seal it every three to four years? The two main reasons for sealing your driveway are: 1.) to make your surface look as good as brand new; and 2.) for the sealer to protect the surface and give it longer life. If your driveway seems to be worn out, then an outstanding sealant will make it look like new again. You can have that shiny black color back with just a little bit of work on a Saturday afternoon.
Over time, asphalt naturally cracks because of the sun’s harmful rays and the coldness of winter. Not sealing it will lead to future problems such as the degradation of the asphalt oil, leaving you only gravel or aggregate, and then water can seep into the material which will result in breakage of the asphalt if the weather freezes. The gravel or aggregate cannot stand alone so without the oil, the asphalt will be damaged and left with holes in it. This is the the cause of potholes that you see in roads and highways. A crack forms in the surface and then water will penetrate into this crack and just sit there. The next time the weather turns cold this water freezes and expands which makes the crack even bigger. As the crack increases in size the sides will start to break off and the holes continues to get larger. Before you know it there is a big void which will just continue to grow if it isn't patched.
A good, top quality sealant will help solve this problem. The best asphalt sealer is, in fact, composed of a different base material, in case you didn’t know. Coal oil is used as a sealant because of its superior capability to bond with the blacktop surface. Coke, a solid carbon material, is used as a heating agent or fuel in steel production and when it is manufactured, coal oil is produced.
The problem with a coal oil based product is it releases volatile organic compounds or VOCs. These are very dangerous in confined spaces and can actually lead to serious health problems. This product should only be used in places where there is lots of fresh air to disperse the VOCs. If you just don't want the potential health and environmental problems with a coal oil product then the next best product is an asphalt emulsion. They are much safer although they don't bond quite as well as the coal tar. If the time comes you have to use a sealer, choose asphalt-based products which contain extra polymers so that these will serve as bonding agents for your driveway.