There are many materials available for asphalt driveway maintenance including emulsified liquids, plastic fillers and solid cold-patches. For a complete driveway rejuvenation, you may need all three. Before tackling any maintenance or repair, check your driveway for these conditions:

• Impressions left by car tires after the car has been parked on the drive overnight. This is an indication of poor construction.
• Heaving or tilting during cold weather, or buckling or cracking with the spring thaw. These are signs of poor drainage.

To repair these troubles, you’ll need a new driveway. Fortunately, such problems are not common. More likely problems are minor cracks, crumbling and chuckholes, which are relatively easy to repair. The procedure and materials used depends on whether you’re repairing cracks, filling low spots, patching or seal-coating your driveway. Your local retailer can help you select the products you need for making repairs.

REPAIRING CRACKS

• You should fill any cracks in a blacktop drive as soon as possible to keep water from getting under the slab and causing more serious problems. Cracks that are 1/2″ and wider are filled with asphalt cold-patch, sold in bags and cans. Narrow cracks are treated with crack-filler, which is available in cans, plastic pour bottles and handy caulking cartridges.
• Use a masonry chisel, wire brush or similar tool to dig away chunks of loose and broken material from the crack.
• Sweep out the crack with a stiff-bristled broom. Your shop vacuum will also work well.
• Use a garden hose with a pressure nozzle to clean off all dust. If the area is badly soiled or covered with oil or grease drippings, scrub it with a strong commercial driveway cleaning agent. For a patch to adhere, the crack must be free of all such things. After using a cleaner, rinse the area with water.
• For a deep crack, fill it to within 1/4″ of the top with closed-cell plastic backer rod or sand before applying a patching compound.
• Apply the crack-filler.

FILLING DEPRESSED AREAS

• Depressed areas, sometimes called “birdbaths,” cause water puddles on the driveway. If not too deep–less than an inch–these areas can be filled so they’re even with the surrounding surface. Sweep away all dirt, hose down the area and remove any oil or grease by washing with a detergent or cleaner.
• The surface may be slightly damp when applying the patching material, but make sure there is no standing water.
• To help the new material adhere to the old, prime the area with emulsified liquid asphalt, which is often simply called “driveway coating.”
• Then, use a trowel to spread asphalt cold-patching material into the depression, filling it level with the surrounding surface. Smooth the patch, then tamp it with a metal tamper or a 5′ to 6′ length of 2×8 or 4×4 lumber. Used vertically, the lumber has the surface area and weight for successful tamping.
• Allow your blacktop patch to dry for 24 hours before seal-coating the entire driveway.

PATCHING POTHOLES

• For potholes, first dig out any loose material and dirt down to a solid base. It’s best to undercut the edges slightly to provide a “key” for the patching material (Fig. 6). Make sure the edges of the asphalt around the hole are firm.
• Clean all dust and debris from the hole and surrounding areas.
• If the hole is very deep, fill it to within 4″ of the top with gravel. Tamp this down firmly.
• You don’t have to work with hot-mix patchers as professionals do–cold-mix patching products do an excellent job of repairing driveways. Fluid cold-patches that come in cans may need to be stirred before use. Use a strong stick or a stirring attachment chucked into your electric drill.
• You can prime the repair area by painting it with emulsified asphalt liquid. Priming helps the new material bond to the old. Then apply the cold-patch material, patting it down occasionally with a shovel or trowel to help compact it and prevent air pockets from forming (Fig. 7).
• Put in a 2″ depth of cold-patch and tamp it firmly or roll it with a garden roller. Add more material in 2″ lifts, tamping each lift. The next-to-last lift should fill the hole to within an inch of the top. Tamp it as shown in Fig. 8.
• Now add more patching material, filling the hole and mounding it slightly above the surrounding surface. Tamp it down as firmly as you can. You can tamp it by hand or by repeatedly running your car’s tire over it (Fig. 9).
• Fill in any low areas with more cold-patch mix. Compact it until it’s even with the driveway surface.
• Allow the repaired area to cure for 12 to 36 hours before driving on it, and give it two to five days to cure before seal-coating the entire driveway.