Asphalt is not a solid fixture to be laid down once and left to the elements, never to be maintained. It is a dynamic material that requires ongoing care for a prolonged lifespan. Sealcoating the surface every two years is therefore critical. While applying sealer is easy enough that anyone can do it with little knowledge of how it works, understanding exactly why asphalt deteriorates and how sealcoating prevents this will better equip you to care for your asphalt—sealcoating, and beyond.
Want to learn how to save money on your property maintenance by repairing your asphalt yourself? Sign up for our free Property Owners Course.
Why does sealcoating asphalt matter?
The sun, moisture, temperature, and wear and tear from traffic all deteriorate an asphalt surface, practically from its installation.
- UV rays from the sun oxidize the asphalt, drying it out and making it brittle rather than flexible.
- Rain erodes asphalt surfaces, causing it to become rough and pebbly.
- Moisture expands in freezing temperatures, prying asphalt apart.
- Oil, gasoline, salt and other chemicals damage asphalt's composition, weakening it.
A layer of sealer applied at the right time is the first step to preventing the elements from gaining a foothold and inflicting costly damage to blacktop. Even the color of a new coat of sealer works to protect the asphalt, as the black of the sealer absorbs more heat and speeds up the melting of ice and snow so they can do less damage.
How does asphalt sealer work?
Liquid sealer pumped through a sealcoating machine and sprayed onto blacktop dries, forms a much-needed barrier.
Asphalt sealcoating works not only to protect the surface from threats above, though. A fresh layer of sealer will also prevent moisture from penetrating its surface, eroding the ground beneath it, and reducing the asphalt’s support.
In fact, water resistance is such a hallmark of a well-protected parking lot or driveway that an easy way to tell if it’s time to reseal your asphalt is to simply pour some water on it. If it beads up, you likely have a while longer before you need to reseal. If it sits on the surface, this means the water is seeping into the asphalt, and it’s probably time for a new coat.
Another easy way to decide whether or not it’s the right time to sealcoat your asphalt is to just look at it! Recently sealed asphalt will have a dark, black color. Surfaces in need of resealing will appear faded, gray, and may even have some pitting, indicating that erosion has already begun.
What asphalt sealer works the best?
The effectiveness of this protective barrier will depend on the quality of the sealer used. There are many types out there, but for the highest quality, you should select sealers marked as containing coal tar and/or “airport grade."
Just ensure this type of sealer is permitted in your area. This chart will help.