Does Sealing A Driveway Stop Weeds Coming Through?

There is nothing worse than pulling out every weed by hand to ensure your driveway stays pristine, only for the little buggers to return − with their friends! Can we prevent this far from ideal reoccurrence by sealing our driveways? 

Sealing your driveway will minimize weed growth drastically by seeping down into the sand between your pavers and hardening it to prevent the weeds from taking root in the driveway. However, it’s vital to prepare the area and apply the sealant correctly for optimal results.

While sealing your driveway can minimize or remove pesky weeds from seeping through the driveway, the quality of the sealant, preparation, and application method is critical to prevent those tiny green heads from reappearing in the pavers or cracks in the driveway.

What Is Sealing A Driveway?

Home in suburbs with circular driveway
Home in suburbs with circular driveway

Before getting to the good part, let’s look at what sealing a driveway will entail.

There are various materials, methods, and reasons for sealing a driveway; the most common include reviving a worn driveway, slowing down oxidation, preventing water penetration, and limiting weed growth −we’ll be focusing on the latter.

Sealcoating your pavement is the process of laying down a protective liquid coating over an existing surface to form an impenetrable barrier. There is a wide range of seal coating materials available; your choice largely depends on the driveway’s material and personal preferences. 

How Does Sealing A Driveway Work?

Sealing your driveway is a process to consider only after the driveway is installed and cured

A contractor or yourself (if you are a DIY enthusiast) will either brush, roller or spray on the sealant over your cured driveway surface:

Paint roller and paint tray being used to seal a tarmac driveway w
Paint roller and paint tray being used to seal a tarmac driveway

The application method will differ from product to product; some sealants are brushed on while others are sprayed on with a high-pressure sprayer:

Note that the sealant products may vary depending on the driveway’s material; asphalt or concrete.

Does Sealing An Asphalt Driveway Prevent Weeds Growing?

Unfortunately, weed infiltration is prevalent, even with an asphalt driveway.

Think of these pesky weeds as opportunists − they invade even the most minor crack or cranny and start to grow with a vengeance! 

While the weeds aren’t actually strong enough to grow through the asphalt material, they love to grow through existing cracks. More so, the weeds can grow their way up from underneath the sealant if you or the contractor do not follow the appropriate steps.

Asphalt naturally retains moisture and heat well − both factors that weeds love − and the sealant protects the seeds from damage; these factors create a perfect environment for weeds to thrive. Therefore, preparing the driveway and adequately applying a high-quality sealant is critical.

Although correctly sealing your asphalt driveway can dramatically decrease the rate of weeds resurfacing, it is critical to point out that weed prevention does not mean you won’t have any weeds growing in your driveway. 

No matter how professionally you apply the sealing, you can still find them resurfacing here or there due to a series of conditions.

How To Seal An Asphalt Driveway To Prevent Weeds Growing

Plants and weeds growing through the cracks in old asphalt
Plants and weeds growing through the cracks in old asphalt

Follow these straightforward steps to seal your asphalt driveway:

  1. Be sure to check the weather forecast. Select a period with a dry weather expectation of at least 48 hours.
  2. Next, thoroughly clean the pavement by removing existing weeds, sweeping, and power washing.
  3. Remove oil stains with a primer and patch the deep holes with an asphalt patching compound; ensure a flat, solid surface.
  4. Then, apply the liquid sealing coat with a squeegee or sprayer (for larger surfaces) over the entire driveway, carefully following the manufacturer’s instructions. Consider using a product like Jetcoat Premium Driveway Sealer, which is often straightforward enough for a DIYer like you and I.
  5. Apply a second coat in an alternating direction the following day.
  6. Allow the sealant to dry for at least 36 hours.

Does Sealing A Block Driveway Prevent Weeds Growing?

Some grass and weeds coming through brick pavers
Some grass and weeds coming through brick pavers

Block paving is another popular driveway choice due to its robust, load-bearing, and cost-effective nature. However, seeds fall into the sand gaps between the blocks, creating a perfect haven to grow and flourish into annoying weeds.

Consider using a sealant to reclaim your Saturday afternoons wasted on plucking out the weeds time and again. While the sealant won’t entirely prevent the weeds from growing between your driveway blocks, it is sure to keep most of the weeds at bay.

How To Seal A Block Driveway To Prevent Weeds Growing

We recommend using a polyurethane sealant for block paving. The extra price paid for this sealant is worth every penny, as it solidifies the sand joints and creates a long-lasting protective barrier on the driveway surface.

Warning: do not use a polyurethane sealant on clay blocks.

Follow these six steps to seal your block paved driveway:

  1. Choose a weed killer depending on how aggressively the weeds grow through your driveway. We generally recommend using a high-quality paving cleaner like NC60 cleaner that will clean your driveway and kill the weeds in the process.
  2. Pressure wash the driveway, and be sure to pay special attention to cleaning the gaps between the slabs. After cleaning the area, allow it to dry fully.
  3. After making sure that the weather forecast doesn’t predict rain for the next 48 hours, you can sand the joints. Place sand between all the gaps and use a small brush to brush the sand into place.
  4. It’s advisable to seal the driveway on the same day as sanding the paving.
  5. Apply two coats of the paving sealant, allowing it to dry in-between applications.
  6. Allow the sealant to dry for two days before allowing heavy trafficking on the driveway.

Does Sealing A Concrete Driveway Prevent Weeds Growing?

A double garage with concrete driveway leading to it and concrete path along side
A double garage with concrete driveway leading to it and concrete path along side

For many individuals, weeds growing through concrete appears counterintuitive. Well, while the weeds aren’t physically strong enough to grow through concrete, they grow through the cracks and damaged areas of concrete paving.

In addition, expansion gaps are a brilliant breeding ground for weeds to grow as the cracks and gaps contain an abundance of soil, nutrients, moisture, and warmth − much like a micro-environment.

Expansion gaps form a break between the concrete paving, preventing stress and cracks by contracting and expanding as the temperature alters.

Sealing the concrete driveway will most definitely reduce the occurrence of weeds, but getting rid of them is highly unlikely as the expansion gaps frequently need resealing to prevent weeds from sticking their heads out between the concrete slabs.

More so, sealing the driveway as soon as you pave it will help by deterring cracks from forming due to oxidization. As a result, there is minimal space for dirt and seeds to accumulate and grow without crannies.

How To Seal A Concrete Driveway To Prevent Weeds Growing

Acting as quickly ensures the best results. If possible, seal the driveway as soon as you lay the paving to prevent weed seeds from sinking their way into the expansion gaps

The most common concrete driveway sealers are acrylic-resin-based; they provide the best performance characteristics cost-wise. In addition, they often contain a blend of epoxies, silicones, or polyurethanes to improve durability and water resistance. 

If your driveway is already installed and the weeds are becoming a problem, follow these guidelines:

  1. Your first step in remedying the infestation is to remove the weeds currently growing in the driveway. So, you can use the old-fashioned route by pulling them out by hand or using a commercial herbicide.
  2. Seal all the cracks with a liquid cement crack filler in the cement paving to prevent future weeds from occurring. Fortunately, cement crack filler is easy to find and relatively inexpensive.
  3. Seal the driveway with a sealant using a squeegee or sprayer. Generally, it is best to apply water-based sealers with a squeegee or roller and oil-based or solvent-based sealers with a sprayer. Ensure you apply two or three coats, allowing each to dry properly. Consider using Penetrating Concrete Sealer for Driveways.
  4. Plan on resealing the driveway every two to three years.

Conclusion

To conclude, sealing your driveways, whether asphalt, blocks, or concrete, is highly recommended to maintain the quality and exemplary neatness you desire.

A sealant might not be a hundred percent effective, but it’s the best attempt to control weeds’ growth. If possible, seal the paving as soon as you lay it to prevent weeds from finding their way into the cracks and sandy sub-base.

About Charlie D Paige

Charlie is a massive DIY fan, with dozens of DIY projects under his belt - ranging from tiling to electrics, and concrete pads to walls. Charlie loves tinkering, seeing how things works, the outdoors and playing with power tools... so is it any wonder that he's completed so many DIY jobs over the years?

Charlie loves spreading his hard-won DIY experience with the world via this blog.