Though asphalt is a tough and durable material, it is still subject to cracks over time. This is especially true if the asphalt has been installed in a climate subject to a freeze-thaw cycle and gets a great deal of traffic. Fortunately, many asphalt repairs are doable by a layperson.
First Steps
Before any cracks can be repaired, they need to be cleaned out first. The homeowner can remove debris or loose asphalt from the crack with a brush or a wet-dry vacuum. Then, they should fill in the crack with a blacktop crack filler. To do this, fit the filler into a caulking gun, and apply a long bead of it into the crack. It usually takes about 10 minutes to set. After that, use a putty knife to smooth out the asphalt surface and compact the filler. In the case of deep cracks, the homeowner should fill the crack with sand, compacting it to about one half inch of the surface before putting in the filler.
If the asphalt has developed a small hole, the hole should again be cleaned out, this time with a wire brush. The unsupported edges of the asphalt should also be broken off and discarded. Then, the hole should be filled with an asphalt patching compound. This repair material is especially useful when the asphalt has broken near a curb.
If the hole happens in the middle of the driveway or walkway, the edges of the hole should be dug out until the patch is the same thickness all around. This makes the repair last longer.
The patch material should be applied with a trowel until there’s a mound about a half an inch higher than the driveway’s surface. Then, it should be tamped down with the end of a board or a tamping tool.
If there’s a large hole in the asphalt, it needs to be filled in with cold patch or cold asphalt. Cold patch is sought after for these jobs because it doesn’t have to be heated if the temperature is above 50 degrees Fahrenheit. Soft and sticky, it has a consistency that reminds people of pizza dough, but it hardens quickly after it’s applied. Cold patch usually comes in 50 or 60 pound bags, so a person may need help handling it.
Again, the hole needs to be cleaned out and the jagged edges smoothed and made even with a cold chisel and a hammer. Then, the homeowner should add enough cold patch for a small mound to remain behind even after it’s tamped. A really deep hole in the asphalt will need to be filled in two stages, with tamping in between. Finally, the homeowner should lay a piece of plywood or a layer of sand over the repaired area and slowly drive their car over it.
Sealing the Asphalt
After the crack or hole is repaired and the patching material cured, the homeowner will want to seal the asphalt to give it extra protection. Sealant usually comes in five gallon cans, which can cover about 250 square feet. The homeowner should know that older asphalt drives or walkways soak up more sealant than newer ones.
First, the surface should be washed with a garden hose or a pressure washer and cleaned thoroughly with a cleanser safe for asphalt. It might be diluted if there aren’t tough stains on the surface. Asphalt sealant can fill in and cover up small cracks as long as they’re no deeper than about one eighth of an inch. The sealant is simply rolled on with an old, disposable push broom or a squeegee. For extra protection, roll on another coat 36 hours after the first one.