Stains and discoloration can make an asphalt driveway look old before its time. Common culprits are oil and fluid leaks from cars, spilled paint or household chemicals, and environmental stains such as from moss or algae.
Cleaning should be attempted before calling in a paving contractor, as minor stains can often be removed with a bit of elbow grease. Use kitty litter or an absorbent material made especially for oil and fluid spill to soak up the excess liquid. Then scrub with a detergent made to break down oils and grease. Pressure washing may also help, especially with paint or other opaque materials that don't soak into the asphalt.
For environmental stains, a good sweep and scrub to remove the algae, moss, and other debris comes first. This is followed by a good scrub with either a detergent or a moss killer. Diluted bleach can also be used to kill moss and algae.
When stains can't be removed completely by cleaning, there are still options available. For driveways in good repair, beyond the stains and perhaps a few small cracks, applying a sealcoat may be enough. Sealcoating darkens the color of the asphalt, which can help camouflage remaining stains. Sealcoating should only be done after cleaning, otherwise, the stain may seep back through.
If there are both remaining stains and more involved damage, then resurfacing may be the better option. Examples of more severe damages include potholes, more severe cracking, and gravel loosening from the asphalt surface. With this method, your paving service first grinds down the top layer of asphalt, then install a fresh layer so the driveway looks essentially new.
Prevention is the ideal way to deal with driveway stains. Sealcoating isn't just used to hide minor stains, it also prevents the stains from occurring in the first place. The coating, which is a mixture of asphalt and sealing epoxies, fills the pores in the asphalt paving to create a waterproof and stain-proof seal. When spills happen, it is much easier to clean them up since the spill won't soak into the paving.
Sealcoats require periodic reapplication. How often depends on several factors, including how heavily your driveway is used and the local climate. As a guideline, it's time to call your paver for a sealcoat application when water no longer beads on the driveway surface but instead soaks in.
Contact a residential asphalt paving service if you are ready for a stain-free driveway.