Once the mixture sets and that heavy oil smell dissipates, there’s nothing like the stark pitch black of a fresh asphalt driveway. Asphalt is affordable, attractive, built to last, and the paving material of choice for many driveways. However, it seems that from time to time, even a built-to-last driveway doesn’t last as long as it should. What happened? What causes asphalt driveways to deteriorate much sooner than we expect them to? Some of it may be in your hands—or your tires, as it were—while other factors lie beyond your control. Let’s explore.
Ultraviolet Light: Ultra-Violent to Driveways
While the sun’s ultraviolet rays can give us a rich tan, they fade almost everything else. Your favorite t-shirts lose a little color from being out in the sun. If you’ve positioned your bookshelf to face windows that get a lot of sunlight, you’ll watch your spines fade from that signature Penguin orange to a sickly yellow.
Out in the driveway, asphalt is not immune to the effects of UV rays. Paving asphalt is a mix of a petroleum binder and an aggregate, such as sand or stones. Oxidation breaks down the bonds that connect oils with one another and the aggregate, causing the material to fade and crumble. If you live in an area that receives heavy sunlight, such as Florida or Arizona, your asphalt driveway will age prematurely. At least your blacktop isn’t dealing with the white stuff we’re about to cover.
Salt: Beware NaCl Without Any Seal
Let’s move north to cooler climes. When winter rolls in and the snow falls, we have to dig ourselves out, and once we’ve shoveled the snow off to the sides, many of us like to throw down some road salt to melt away the remaining snow or ice.
It’s often a necessary step, but without proper sealants on an asphalt driveway, the compounds in road salt can expedite the degradation of the petroleum by increasing how many thaw/freeze cycles the pavement undergoes. If you want to make sure your driveway survives those brutal northern winters, give it proper sealing. Don’t pour salt into your driveway’s wounds.
Tree Roots: A Growing Concern
We all love a street with old-growth arbors lining the parkway between sidewalk and street. However, when that old growth goes unchecked, far-reaching roots can make their way beneath your driveway and cause problems. These thirsty roots will grow far in search of water—even underneath the pavement. Part of what causes asphalt driveways to deteriorate before their time is this pressure from below, causing cracks that need filling. Save your driveway without sacrificing your trees by installing root barriers that divert roots from your driveway and prevent premature deterioration.
Asphalt driveways require a little extra care to keep their lifespans long. Don’t let that dissuade you—they’re still an excellent choice for paving. Consider a strong sealant to protect against wear, sunlight, and salt for a lasting solution.