FAQ: Asphalt / Blacktop Sealing

Can animals or barefooted children be harmed by walking through wet asphalt sealer?

Most Gardner products are water based asphalt products that in general will not cause skin irritation. However, anyone with sensitive skin should avoid contact. If the sealer is still wet, rinse area immediately with water. For dried particles, try a water based citrus cleaner designed for washing skin, as this should remove any excess.

A second non-health issue is tracking wet sealer into the house. Asphalt sealers can stain, even if cleaned up while wet. Anyone who comes in contact with wet sealer should remove their shoes and other clothing that has sealer on it before they come in contact with fabric, wood, paint, tile, or other valuable household surfaces. If the driveway sealer has dried on children’s feet or pet paws it will not track, and it will eventually wear off.

Can I seal a blacktop driveway myself, or should I hire a contractor?

Driveway sealing is a great project to take on yourself, but many contractors do an excellent job. When used as directed, both homeowners, maintenance personnel, and contractors will get excellent results with our products. If you hire a contractor, make sure:

• They use quality products
• They do not thin the sealer
• That they prepare the surface properly (including cleaning and degreasing, patching cracks and holes)
• They apply the sealer at the correct temperature (65° F and rising)
• Spread it manually to avoid puddling

When doing it yourself, follow the label instructions thoroughly to do the job right. We have some great application instructions available on this site.

Do I need to patch cracks or holes before sealing?

Yes, large holes and cracks will get worse over time. Sealers are not intended to repair them. Gardner offers the best asphalt driveway repair products in the industry. They are 100% tested and proven with all Gardner driveway sealers and provide the longest lasting protection.

How can I tell when it is safe to walk and drive on?

First, wait the appropriate time, then use a gloved hand or cotton shop towel to rub/touch the surface. If black appears on the glove, avoid driving on it. Press into the surface and ensure that the sealer is completely dried all the way through, not just on the surface. For cracks, insert a toothpick into the crack. If it comes out black and wet, it has not fully cured. Driving or walking on wet sealer can ruin the finish and cause tracking onto garage floors and other surfaces you contact.

How do I fill medium to large holes?

Gardner Blacktop Drive Patch is designed to patch large cracks and small holes from ½" to 3”. Follow label directions for detailed instructions. This asphalt and sand mix, trowels to a smooth finish. RePave Pothole Patch is designed for holes larger than 4” up to large potholes. This product can be used year round and after application is ready for traffic immediately.

How do I remove weeds, grass and other plants growing in my driveway cracks?
There are a number of commercial weed killing products designed for killing weeds, but they typically take days and must be completely dry before sealing. A faster approach is to use a screwdriver or other narrow weed puller to dig out the entire plant.

How long should I wait before applying a second coat?

A second coat should be applied after the first coat has cured. Under ideal conditions, typically we recommend waiting 4-12 hours, and until the first coat is fully dry and cured all the way through the film. In optimal conditions, if the driveway is sealed early in the morning and the entire driveway is in full sun and is fully dry, you may apply a second coat the same day. However, many factors, including thick or uneven coats, cooler surface temperatures, high humidity, areas of shade, overcast conditions, and poor air flow, each can slow dry times and require a longer re-coat time.

To improve dry times, do not let any product "pond" or puddle up. Thinner coats that completely cover the surface dry faster, and multiple thin coats perform better than single thicker coats. Curing times can vary. See and follow label directions for more information about your specific product.

How much sealer do I need to buy for my driveway?

Coverage rates will vary by sealer and by the condition of your driveway. A driveway that has not been sealed recently will require more sealer to fill in pores and cracks that have developed. Gardner has developed a coverage calculator to help you decide how much sealer to buy for your driveway. You can access it by finding a product and clicking on the coverage calculator.

Please note that if you get too much coverage, you are applying too thinly; conversely, too little coverage may mean you applied too thick, unless your surface is very rough or very porous.

Always buy more sealer than you need, for a few important reasons

    •    First, if you run short and need to stop to get more, the sealer already applied will cure and there will be a visible line where you stopped to get more sealer.
    •    Second, the application temperature and other conditions will be different when you re-start, creating another “change” in the appearance of the sealer.
    •    Finally, if you stop to buy more, you risk getting product from different batches or different brands than you started with.

How soon after installation can a new asphalt/blacktop driveway be sealed?

We recommend you wait at least 6 months including one full summer season prior to sealing to allow it to fully cure and weather. After 6 months use the water bead test to determine if your driveway is ready to be sealed: spray water across your driveway; if it forms beads, it is not fully cured and not ready to be sealed yet, so you’ll have to wait a bit longer.

How soon after sealing can I drive on my blacktop driveway?

Under most conditions you can drive on your driveway 24-48 hours after the last coat is finished. There are a few issues to note that affect dry time:
    1.    Areas in full shade will take longer than areas in full sun.
    2.    Cooler temperatures below 80° F and higher humidity above 50% can add up to 12 hours to the full cure time.
    3.    Driveways with many cracks take longer; the more cracks and the deeper the cracks, the longer it takes to cure.
    4.    Thicker coats slow dry time. We always recommend two thin coats for best results.

I have a concrete sidewalk and brick pavers along my driveway. Can I seal over these areas? If not, how do I avoid getting asphalt sealer on them?

Gardner driveway sealers are meant only for blacktop/asphalt surfaces, not for concrete or brick. To minimize the chance of getting asphalt sealer on these areas, you can first mask with tape and plastic sheeting or a drop cloth along the affected edges. Another option is to carefully “cut in”—or coat a six-inch wide strip along the edge of your driveway using a smaller brush to coat the driveway edges.

As a side note, be careful not to place lids, applicators, wiping clothes, or pails of sealer on a concrete or brick area and avoid spills. Also be aware that your wet shoes can track asphalt sealer onto garage floors and sidewalks, so they should be removed before walking on these areas.

I have multiple batch codes, how do I ensure all product is consistent and provides a uniform result?

It is always best to mix the buckets to ensure proper sheen from one pail to the next, just as you would with house paint. This can be done by pouring half of one pail into half of another pail.

I have spilled sealer on an area that I shouldn’t have. What is the best way to clean it up?
All of our driveway sealers will wash off with soap and water when the sealer is still wet. However, if it has dried there are a couple of ways to clean it up. There are a number of high performance citrus-based cleaners available at automotive stores and many home center and hardware stores that work to dissolve dried coatings.

I purchased some sealer in the fall and want to store it in my garage to use in spring. Any concerns?

Gardner sealers are water based, so they cannot be stored where they will freeze. If the product freezes, it is ruined, and will be very difficult to remix. If the product does freeze, do not use it. If the product is protected from freezing and stored in a heated room at 50 degrees or higher, you should be fine. Driveway Sealer should be used within 1 year of purchase.

I’ve tried using a paint stir stick, but is there an easier way to mix 5 gallon pails?
First, we realize that traditionally stirring has been the most difficult part of the asphalt driveway sealing project. That’s why Gardner has created patented no-stir driveway sealers to make your job much easier.

However, if you buy one of our E-Z stir products, there are some techniques that make stirring even faster and easier.

    •    First, before opening the pails make sure the lid is securely fastened. Then flip over the pail and store on its lid for at least 24 hours prior to using the product. Flip over and shake slightly before opening the lid. The flip back over and stir. Mixing should be much easier.
    •    Second, you can use an empty pail to pour two or more pails together back and forth (a process called “boxing.”) This is particularly useful to achieve a uniform finish if you are not sure whether all of your pails came from the same original batch.
    •    A third option is to buy a mixing blade attachment for your power drill, available at many hardware stores and home centers.

If I use a squeegee on my driveway, how do I do the edges? A squeegee seems too big and clunky for trimming around the edges.

Rubber squeegees are your best applicator, but avoid plastic ones—they can skip and fail to give you a precise edge. But for even more precise control, try a broom or brush designed specifically for driveways. Also, you can mask off areas that you want to avoid coating with sealer by using plastic sheeting or drop cloths (as you would when painting). However, make sure you tape down the edges—failing to do so will cause sealer to wick up under the sheeting or drop cloth.

Is an asphalt sealer the same thing as a blacktop sealer? What about tar?

A blacktop driveway and an asphalt driveway are the same thing—asphalt is the more “technical” term. Asphalt is naturally black in color, so you’ll hear sealers referred interchangeably as “blacktop sealers” or “asphalt sealers.” However, the “tar” terminology is not applicable to Gardner brands. It refers to an ingredient called Coal Tar. Gardner products have been upgraded from older coal tar-based technologies into better performing asphalt based formulations.

Should the driveway surface be hot or cold when applying sealer? Wet or dry?

A hot, dry driveway above 95° F will dry to fast; the result can be a very uneven finish. We recommend cleaning the surface first using a driveway cleaner, which also serves to cool off the surface. Make sure there is no puddled water on the driveway before sealing.

If the surface is too cold means the sealer will not set and cure properly. For best results we always recommend application at 65° F or higher for several hours before application, to ensure the surface is warm enough to allow a proper protective film.

Shady areas, high humidity or cloudy conditions can slow the cure time of the sealer, so additional dry time between coats may be needed.

What is the best temperature and weather to seal a driveway?

The best sealing weather is in the morning hours with temps between 75° F to 90° F, with sunny clear skies and no rain. However, sealers can still be applied when the driveway surface temperature and air temperature are at least 65° F and rising. The temperature should not drop below 60° F during the curing process (24 hours).

Don’t wait until fall to seal the driveway from ice and snow, in fact it’s important to seal it against rain and UV rays that can damage asphalt and create cracking and crumbling. So sealing your driveway during any month when temperatures and weather are appropriate is beneficial to protecting your driveway surface.

What tools will I need for my driveway sealing project?

CLEANING: Clean with blower or broom. Then clean driveway with a driveway cleaner with your garden hose to clean and prepare the surface.

APPLY SEALER with a rubber squeegee and/or bristled broom. Plastic squeegees and paint rollers are not recommended.

What's the best way to fix a small crack

Gardner® Blacktop Crack & Joint Filler is our best, highest flexibility crack filler, ideal for cracks and joints up to 1” wide. This product also works great for expansion joints. Dries fast.

What's the best way to fix larger areas of cracks?

For larger areas of cracks ½" – ¾", fill them with Gardner® Elastomeric Crack Filler. This product comes in a 1 gallon jug with an E-Z Pour spout. Applies quickly and easily.

Why do I need 2 thin coats? Won’t one thicker coat work?

Applying two coats of any sealer will dry and create a better finish much better than one thick coat. These sealers are water based, and they cure and form a film primarily during the evaporation of water from the coating. A thin coat will evaporate much faster and create a single uniform layer. A second thin coat will fill in areas not filled by the first coat and create a deeper, richer, more uniform coat. Single thick coats cure less evenly, have a tendency to puddle, and are prone to tracking.

Why do I need to stir driveway sealers?

The good news is that now you don’t have to stir if you use Gardner’s premium no-stir gel formulas. These patented formulas keep all the particles in suspension, so you get an even finish without stirring. However, it is recommended that all driveway sealer buckets are turned upside-down before opening the container. This will ensure proper dispersion for gel sealers, and it makes all other driveway sealers much easier to mix in.

If you buy driveway sealers that still require stirring, the main reason for stirring is to mix together particles that settle naturally during shipping and storage. Failing to stir these sealers can create very uneven color and finishes, gritty areas and slick areas, areas that have little protection, uneven wear, etc.