The two main issues when it comes to asphalt repair are cracks and holes. Although they are both similar, they need to be repaired in different ways. It is best to do any repair in warmer weather, since asphalt becomes more pliable and easier to work with. A little moisture or dampness from cleaning will not affect hole or crack filler, but as a general rule, keep the area as dry as possible.
Cracks and holes
The only way to repair cracks is with a rubberised asphalt filler. This can be obtained at any hardware store and will fit in a caulk gun and is easily dispensed. If possible, prime all cracks and holes with a liquid asphalt compound, commonly known as "driveway coating," as this will allow more gripping power between patch and drive, and create a better and stronger bond.
Pull weeds from cracks and holes, remove any loose particles of asphalt, then use a water hose to blast dirt and debris from them. Any crack that is deeper than 1/4 inch can be filled with sand up to that depth. If you have a 2-inch-deep crack, fill it to 1 3/4 inches, and then lay the rubberised asphalt filler on top of that. If your cracks are greater than 1/2 inch wide, consider them as holes and fill them in with a standard cold-press compound. You can buy cold-press compound at any hardware store. Press the compound into the larger crack or hole, using a trowel, and then tamp it down to level it off. You can also drive back and forth over a repair to make it level.
Depressions in the asphalt, sometimes referred to as "birdbaths," are uneven areas caused by settling. The depressions often collect water. As long as they are less than 1 inch deep, they are repairable.
Use a broom to remove any dirt and debris, hose down the area. If the depression is oily, remove oils with a stiff brush and dishwater detergent and rinse thoroughly. Prime the area first with driveway coating to enhance the bond between patch and driveway surface. Use cold-patch asphalt to fill in the depression. Once filled, even out depressions by driving a car over the top. Place a board down over the asphalt patch if too much begins sticking to the tires.
You can effectively repair cracks, holes and small depressions However, there are times when driveway repair isn't possible. If your car tires have left deep impressions in the surface, it is a sign of poor workmanship when the drive was laid down, and it cannot be repaired.
An unstable surface where the drive heaves or tilts in cold weather, or worse, when it actually buckles in places due to the spring thawing season, tree roots or any other catastrophic event, compromise in the surface. The only repair for a situation like this is to replace the entire driveway.
As a matter of course, after you have made driveway repairs, brush or squeegee a sealer over the top. You can seal cracks right away, but holes and depressions need time to cure first. Follow the manufacturer's directions, but generally, depressions can be sealed in about 24 hours. Holes can be sealed within 12 to 36 hours. Afterward, allow holes to cure for an additional two to five days before sealing the entire driveway, according to the manufacturer's instructions for the type of sealer you are using.
Never leave weeds or debris in a crack or hole. You won't get proper adhesion from the patching medium. Don't use a torch to seal cracks. Asphalt is petroleum-based and so is the sealer, so all you'll accomplish with a torch is to burn the sealer and possibly start a fire.
Sealers are not made to patch holes. If you fill a crack with sealer, it may look good initially, but the crack will reappear. The only way to seal cracks is with a rubberised compound, and the only way to fill in holes or depressions is with cold-press asphalt.