A driveway with a rich, jet-black finish boosts the curb appeal of any home. But there are plenty of other important reasons to seal coat your driveway. Seal coating protects your asphalt driveway from the weather and from chemicals such as oil or gas. And keeping your driveway maintained extends the life of your driveway, eliminating the need for frequent repaving.
The Benefits of Seal Coating
A good-quality driveway sealer is blended with an acrylic co-polymer latex modifier to increase bonding, flexibility, and durability. A good sealer offers these benefits:
- Protects against the sun's ultraviolet rays that crack and dry out asphalt
- Resists the deteriorating effects of gasoline, oil and other harsh chemicals<
- Helps prevent water penetration and resulting weather damage — especially freeze-thaw cycles
- Restores the rich black finish, which is the top reason most people seal coat their driveways
For best results, apply sealer on a dry, sunny day when the temperature is 70 degrees Fahrenheit or above. Cooler temperatures and/or high humidity can lengthen curing time.
Do not apply sealer when rain is expected within 24 hours of application. Temperatures must be 50 degrees or above for at least 24 hours after application. Rain or cooler temperatures within 24 hours of application may irreparably damage the coating.
Curing time varies with the weather. Sealed areas can usually be opened to traffic after 24 hours. Test before use.
The Secret to Success
To ensure a good-looking, long-lasting seal coat, properly prepare the worn asphalt driveway surface before applying driveway sealer and always use a quality blacktop emulsion. Trim grass near the driveway before starting.
Sealing is not meant for use on concrete surfaces. New blacktop surfaces must to cure for one year before seal coating.
All You Need
- Broom with stiff bristles
- Tamper, 4x4 or plywood
- Hammer and concrete chisel
- Applicator, either brush or squeegee style (roller applicators can apply a coat that is too thick, leading to tracking and curing problems)
- Spackling knife
- Garden hose
- Scrub brush
When choosing a seal coat product, you can choose between a filled formula (sanded) and an un-sanded formula. Filled products use sand as an ingredient to create a textured surface with additional traction. The sand is especially good for sloped surfaces and helps prevent falls. It can also help fill hairline cracks. Un-sanded products are generally less expensive and provide a smoother finish.
Read instructions and caution information on sealer container before buying. To determine how much sealer you need, either measure the square footage or estimate how many full-size cars or SUVs can be parked side to side from one end of the driveway to the other. You need one 5-gallon pail of sealer per 350 to 450 square feet or for every two car spaces.
- Strong detergent or cleaner formulated for concrete and asphalt
- All-weather blacktop patch, if the driveway has potholes
- Pourable blacktop crack filler or caulk for cracks up to half an inch wide
- Trowel-grade filler for cracks more than half an inch wide and for dips, uneven areas and depressions.
If you follow this repair program, you might want to set aside two days for the project. The first day is for making small repairs, which allows enough time for those repairs to cure before you apply sealer on the second day.
1. Clean off dirt, leaves and other loose debris. Sweep the driveway thoroughly and then hose it down. Dust, dirt, leaves and even tree sap affect both the bond and the color of the new sealer.
2. Remove oil and grease. Use the spackling knife to scrape thick grease and oil from the surface. Remove remaining buildup with a concrete and asphalt driveway cleaner or a strong detergent. Deep stains might need a second cleaning.
3. Repair potholes and cracks. Repair potholes and deteriorated areas, using an all-weather blacktop patch. Prepare the repair area according to container directions. Use the hammer and chisel to straighten the edges of potholes. Pour the material directly from the container into the patch and then compact the material with a tamper or the end of a 4x4. The better the compacting, the better the patch.
Clean all loose debris and dust from cracks. For cracks up to half an inch wide, use a pourable blacktop crack filler or caulk. For wider cracks, use a trowel-grade crack filler — you can smooth dips, uneven areas and birdbath depressions with this material.
Allow asphalt repairs to cure before applying pavement sealer.
4. Seal the surface. You can apply driveway sealers while the driveway is damp, but remove all standing water. Pour a small amount of sealer onto the driveway and spread with a brush or squeegee applicator.
Spread the sealer evenly with the squeegee. It's important to maintain a uniform thickness of the sealer. A thin coat (1/16 to 1/32 inches) is best.
Use the brush to redistribute any excess material. Brush the coated surface in one direction, pulling the excess material toward you and the unsealed portion of the driveway. Brushing eliminate puddles that can cause tracking.