Asphalt Driveway Sealing: Crack Filling, Application, and Timing

When to Seal

New asphalt should cure for 6 to 12 months before the first sealcoat. The oils in fresh asphalt need time to evaporate; sealing too early traps them and creates a soft, sticky surface.

Reseal every 2 to 3 years, or when the surface color fades from black to gray and you can see aggregate (small stones) exposed at the surface. Those are signs that the binder is wearing away.

Do not seal over new cracks without filling them first. And do not seal driveways that have structural failure — large alligator cracking, deep potholes, or sections that have sunk. Sealcoat is a surface treatment, not a structural repair.

The ideal conditions for sealing: air temperature above 50 degrees F, no rain in the forecast for 24 to 48 hours, and the driveway surface is completely dry. Spring and early fall are the best seasons in most climates.

Crack Filling

Fill cracks before sealing. Sealcoat bridges hairline cracks (under 1/8 inch) but anything wider needs dedicated crack filler. Left unfilled, water enters the cracks, freezes, expands, and widens the damage each winter.

For cracks up to 1/2 inch wide, use pourable rubberized crack filler. Clean debris from the crack with a screwdriver or crack cleaning tool, then fill to slightly below the surface level. The filler needs to be flush or slightly recessed so sealcoat flows over it smoothly.

For cracks over 1/2 inch, use backer rod (foam rope) to fill the depth, then top with crack filler. This prevents the filler from sinking into deep voids and wasting material.

Let crack filler cure according to the manufacturer's directions — typically 24 to 48 hours — before applying sealcoat over it.

Surface Preparation

Preparation determines 80 percent of the outcome. A clean, dry surface lets the sealcoat bond. A dirty or oily surface causes the sealcoat to peel.

Start with a leaf blower or stiff broom to remove loose debris. Then use a pressure washer at 2,000 to 3,000 PSI to clean the entire surface. Pay attention to oil stains — sealcoat will not bond to oil. Scrub oil spots with a degreaser and stiff brush, then rinse.

If oil stains are deep, apply an oil-spot primer before sealing. This creates a bond layer between the contaminated asphalt and the sealcoat.

After washing, let the driveway dry completely. This usually takes a full day in warm weather. Moisture trapped under the sealcoat causes blistering and peeling.

Sealcoat Application

Two thin coats outperform one thick coat. A single heavy coat takes longer to cure, stays soft longer, and is more likely to show roller or squeegee marks.

Stir the sealcoat thoroughly before use. The solids settle to the bottom of the bucket during storage. Stir with a paint mixer on a drill until the consistency is uniform throughout.

Apply the first coat with a squeegee or broom applicator, working in one direction. Spread a thin, even layer — you should still be able to see a slight texture in the asphalt through the first coat. If the coat is opaque and glossy wet, you are applying too much.

Let the first coat dry for 8 to 24 hours depending on temperature and humidity. Then apply the second coat perpendicular to the first. This crosshatch pattern ensures even coverage.

Spray application is faster for large driveways. Pump sprayers designed for sealcoat produce a more even coat than a squeegee but require practice to avoid puddles and misses. Most DIY jobs use the squeegee method.

Curing and Traffic

Keep foot traffic off the sealed driveway for at least 24 hours. Keep vehicles off for at least 48 hours, longer in cool or humid conditions.

Sealcoat reaches full hardness in about 30 days. During that first month, avoid parking in the same spot every day — hot tires on fresh sealcoat can leave marks.

Barricade the driveway entrance with cones, sawhorses, or caution tape. A neighbor's car parked on wet sealcoat will ruin your work and their tires.

Frequently Asked Questions