Potholes on the street can breed smaller potholes in your driveway or even a walkway. Fortunately, you can fix small potholes. This Fix-It Guide on asphalt repair tells how asphalt works, what often goes wrong, how to identify an asphalt problem, and what parts and tools you will need to fix cracks and potholes. The guide then gives simple step-by-step instructions for how to fill a minor asphalt crack, how to fill holes in asphalt, and how to clean and seal an asphalt surface.
How Does Asphalt Work?
Asphalt is a dark brown or black tar-like substance found in petroleum deposits. Heated up and mixed with crushed rock or other materials, asphalt becomes a relatively hard, smooth surface to support cars and people. In addition to being used on public roads, asphalt is popular for paving residential and commercial driveways, walkways, and paths.
Don’t be taken in by unscrupulous workers who come to your door and offer to repair your driveway for a small fee. All they may do is spread used motor oil over the driveway. The repairs they perform may not last any longer than it takes for them to leave town.
What Can Go Wrong with Asphalt?
Asphalt can crack, especially in cold areas where freeze/thaw cycles are common. Small cracks let in water that will freeze and expand, causing existing minor damage to become major. Periodic sealing will help keep cracks from starting, but won’t prevent damage caused by settling of the ground or by improper installation of the asphalt.
How Can I Identify an Asphalt Problem?
- If an asphalt driveway, road, path, or sidewalk develops a small crack, you can fill it with asphalt-based caulk (see below).
- If the asphalt has already developed a hole, you can patch it with asphalt patch (see below).
- If you want to keep asphalt in good condition, you can periodically clean and seal it (see below).
What Do I Need for Asphalt Repair?
- Shop vacuum
- Putty knife
- Caulking gun
- Asphalt-based caulk or sealer
- Rubber gloves
- Wire brush
- Asphalt patching compound
- 2×4 piece of lumber
- Thick (3/4 to 1 inch) plywood
- Garden hose with sprayer or pressure washer
- Squeegee or push broom
- Household cleaner
What Are the Steps to Asphalt Repair?
Fill a minor asphalt crack:
- Sweep out loose material or vacuum it up with a shop vacuum.
- If the crack is deep, fill it with sand, and compact it to within 1/2 inch of the surface.
- Use a caulk gun to apply a continuous bead of asphalt-based caulk. Follow the instructions for drying time (usually about 10 minutes).
- Compact and smooth the surface with a putty knife, being careful not to spread caulk too widely.
Fill a small hole in asphalt:
- Brush out any loose material or vacuum it up with a shop vacuum.
- Clear away loose chunks and break off any unsupported edges of the old asphalt.
- Spread asphalt patching compound in the hole using a trowel until the compound is mounded slightly higher than the driveway.
- Use the end of a piece of lumber to tamp the patch down, level with the driveway surface.
Fill a larger hole in asphalt:
- Remove any loose debris and smooth jagged edges around the hole with a hammer and chisel. If the hole is deep you can place and pack solid debris (rocks, etc.) in the hole as a foundation for the asphalt patch.
- Fill the hole about half way to the top with asphalt patch and tamp it down with the end of a piece of lumber.
- Fill the hole to slightly above the surrounding asphalt.
- Place a piece of thick plywood over the patch.
- Drive a car slowly over the plywood to compact the patch.
Does your asphalt driveway need resurfacing? To find out, pour water on it on a hot day and watch to see if runs off quickly, which it should do, or if it seeps in, meaning it needs resurfacing.
Clean and seal an asphalt surface:
- Use a pressure washer or a hose with a pressure nozzle to wash the asphalt surface.
- Apply full-strength household cleaner on any remaining stains.
- Spread on a thin coat of sealer with a squeegee or old broom.
- Allow the sealer to dry for 24 to 36 hours before applying a second coat if needed.
How much asphalt sealer do you need? Five gallons will cover a typical 10-feet by 25-feet driveway, depending on how porous the surface is. Check the sealer label for coverage estimates.