Seal New Asphalt Driveways Immediately
Do not seal new blacktop driveways right away. The asphalt contains oil that needs to evaporate before the sealing process. Sealing the oil into the blacktop leaves a soft surface that dents from pressure, such as that from a bike kickstand. New asphalt needs at least 90 days, at a daytime high temperature of 70 degrees, for the blacktop to harden properly before sealing.
Clean the Driveway
A new or existing driveway requires a thorough before sealing. Scrub oil stains with a grease-cutting cleaner, and rinse the soap and stain away with a garden hose. Rinse the entire driveway with a hose, removing caked-up dirt and debris. Sweep excess water from the driveway with a stiff-bristled broom.
Before sealing, patch cracks or dips in the driveway that may have formed over time. Patch the affected areas with a patching compound. For deep cracks, fill with sand to 1/2 inch from the top of the blacktop, and fill the rest of the way with the compound. Allow the compound to dry and set for one week before sealing the driveway.
Use an Approprite Driveway Sealer
Asphalt driveways need a sealer that protects against gasoline and oil drippings. Considered the best, according to Tim Carter from Ask The Builder.com, an acrylic sealer lasts longer and withstands heat or air erosion. A concrete driveway requires a sealer that allows moisture to escape, especially in colder climates. Apply a film-former sealer with solvent-based acrylic once a year to concrete driveways. Concrete driveway sealers wear off faster than sealers for asphalt, allowing for once-a-year applications.