Asphalt is an inexpensive and durable alternative to concrete. If you need to replace an old concrete driveway with asphalt, you probably have a few questions.
Can Asphalt Be Installed Over Concrete?
It's not advisable to install asphalt over concrete. The most obvious reason is that chances are that the concrete is damaged if you are installing new asphalt. Damage like cracks are often caused by shifting concrete, which can affect the asphalt. This means that any cracks that were in the concrete will likely soon appear on the asphalt if you attempt to use the old driveway as a base.
Even concrete in good condition can cause asphalt problems. Concrete isn't as forgiving as asphalt, so it often has expansion joints installed. These joints move with thermal expansion, which they will continue to do beneath the asphalt. The result is cracked asphalt along the joints.
Will the Concrete Base Be Reused?
In most cases, the concrete base cannot be used as-is. Concrete is much less flexible than asphalt, which is part of the reason that it is prone to cracking. Often, concrete installers create a very simple base and pour thicker slabs of concrete since its lack of flexibility makes up for a weak base. Asphalt is more flexible, which makes it less prone to cracking but only if it is one strong base that doesn't shift too much.
This doesn't mean that the old concrete base must be removed completely. Often, an asphalt installer can use the old concrete base as the beginning of the new asphalt base. It will be leveled and compacted, and then additional material may be brought in to shore it up and make it stronger before the asphalt installation.
What Happens to the Old Concrete?
Fortunately, concrete can be recycled. After it is broken up, your asphalt service can haul it off to a concrete recycler. Check with your paving company to make sure they offer this option.
Recycling of concrete is relatively simple, as it is generally crushed and turned into aggregate or gravel. This is then used in future paving projects or as a landscaping material. Even the asphalt left over from your paving project can be recycled into new asphalt, so few if any materials go to waste when you choose to have a new asphalt driveway installed.
Contact an asphalt paving company near you if you are ready to replace your old concrete driveway.