Sun Oxidation is when the sun starts drying out your Asphalt.  It starts months after the original install of your asphalt parking lot.  It starts by drying out your surface of your asphalt (if not sealed) and it slowly starts to harden your asphalt.  Asphalt is a flexible pavement unlike concrete which is a non flexible pavement.  As months and years go by your asphalt starts to become brittle if not sealed from the sun.  It becomes less flexible when not treated with seal coat.  This causes your asphalt to crack in many different areas due to it being more non flexible than flexible from the sun oxidation process.  Seal coat reverses this trend.  In addition, the small rock mixed in with the asphalt during original install starts to pop off the surface of your asphalt due to it drying all the asphalt adhesives on the top layer.  This is called pitting.  If your lot has not been sealed in a while you can witness this on every parking lot by seeing small loose rocks scattered throughout your parking lot.  Sealing your parking lot completely reverses this trend and protects your asphalt from Sun Oxidation.


Water can erode any surface and any material known on earth.  Take a look at the Grand Canyon and see how water is shaping the landscape.  Think of any cracks on your parking lot as a small example of the Grand Canyon.  As water travels across your parking lot it normally will travel the path of least resistance which is along the cracks of your parking lot.  During the warmer months the water starts carving out your cracks and it starts traveling underneath the asphalt.  It's important to know that 90% of the strength of your asphalt is the base underneath it.  As water starts traveling underneath your asphalt it weakens this base by washing out the smaller fines of the rock base.  This creates the base to get soft and creates air pockets underneath your asphalt.  This is where your next pot hole will be created on your lot.  In the winter it is much worse and the eroding process is much quicker.  During the day the water gets in your cracks and gets underneath your asphalt during the winter.  The real damage is caused at night when this water freezes and then expands due to the freeze thaw process.  This process repeats itself for 4 months every night over the winter.  If you seal coat your parking lot it greatly reduces the amount of moisture that gets underneath your asphalt and fills the cracks to the point that the water is traveling over seal coat and not letting the water get underneath your pavement through the cracks in your asphalt.


The important affect of seal coating your lot is it greatly reduces the chance of you having patchwork problems in the future.   Patchwork can easily cost more money than getting your entire lot seal coated and striped.   Keep your lot sealed will give you cosmetic value to your property, extend the life of your asphalt and save you money by GREATLY reducing the chance of needing asphalt patchwork as your asphalt ages.