Dan The Paver

Why It’s Better to Avoid Paving Asphalt Over Concrete

There has long been a debate about whether driveways should be inlaid with concrete or asphalt. But over the years, asphalt has proven better for driveways for a few of the following reasons:

  • It is easier and quicker to install
  • It has better weather resistance
  • It is more cost-effective. 

However, if you already have a concrete driveway, this might present a challenge. You might be wondering whether it’s possible to lay asphalt over concrete. The answer: You certainly can. It is cheaper than breaking up and digging out the concrete slab to replace it with asphalt.
That said, many contractors and pavers will tell you that it is always better to remove the existing concrete first—for several reasons. If you remain unconvinced that you should remove your concrete slab, read on. We will talk about why it’s a better choice. 

There is a subbase for asphalt, specifically

The subbase for asphalt isn’t the same one for concrete. Without a subbase made for asphalt, you may expose your build to the risk of structural weakness. This is because there is no way to tell whether the base under the concrete is ill-prepared for the requirements of an asphalt driveway. 
You may end up experiencing expansion joints in the concrete, which will require expensive repairs in your asphalt driveway. Even just minor shifts in the ground can cause cracks in the asphalt with the wrong subbase. 

The difference between asphalt and concrete subbases

One key difference between the subbase of asphalt and concrete is that asphalt needs a semi-flexible and permeable base. This helps the binder take hold of the aggregate materials, providing strength and stability in the paving. It also keeps the materials tightly packed together while allowing a level of permeability that better displaces heat and other fluids. It also allows for greater distribution of forces throughout the structure without cracking. 
On the other hand, concrete needs a rigid subbase before the rigid paving is placed on top. That means it cannot take the shifting and distributed forces from being placed under asphalt. It might cause cracking and major damage to the system if exposed long enough to such forces.

You’ll shorten the lifespan of your driveway

Without removing the concrete slab, you are less likely to breathe new life into your driveway and more likely to shorten its functional lifespan. It will cost more to repair your asphalt driveway again and again since it doesn’t have the support it needs from having the right subbase. 
With the right base, pavers assure that your asphalt paving will last longer and require less maintenance. While concrete and asphalt can work together, they are not suited for use on top of each other. 

In conclusion

When constructing or remodeling your new home (your driveway, particularly), it is crucial not to cut any corners. It might be cheaper to hire a paver to lay out all the asphalt over your current driveway, but you will leave yourself open to expensive repairs down the line. As such, it is important that you build your asphalt driveway from the ground up to ensure that it lasts longer and is better able to resist damage.
If you’re looking for a Monmouth-based paver, give us a message at Dan The Paver. We are a family-run business with years of experience and service in the Monmouth area.