An asphalt driveway is solid and durable and should last for many years before it needs major repair work or outright replacement. However, this doesn't mean an asphalt driveway is indestructible!
The cost of replacing an asphalt driveway will depend on the type of asphalt you choose, the thickness of your new pavement, and if you need to have the current driveway torn up and replaced versus merely having a new layer of asphalt poured.
To better understand your potential costs for a new asphalt driveway, it's useful first to note some information about asphalt itself, as well as how it gets damaged. You can then better understand your options for replacing a residential asphalt driveway and know what to discuss with a paving contractor.
What is asphalt?
Like concrete, asphalt is made from a mixture of cement and aggregates. The adhesive used for asphalt is called bitumen, which is a dark, sticky substance derived from crude oil. This bitumen is heated and mixed with fine aggregate, usually sand or crushed rock.
While it's still warm and pliable, this bitumen mixture is poured onto a layer or foundation of thicker aggregates, usually made from crushed rock or gravel, and then rolled or pressed into place. As the bitumen mixture cools, it hardens and adheres to the aggregates under it, and becomes asphalt.
Is all asphalt the same?
As with concrete, asphalt mixtures are all made individually. Some batches might have a higher concentration of a fine, sandy aggregate, which creates a smooth blacktop surface, and which is preferred for residential driveways.
Other asphalt batches are made with thicker aggregates or a higher concentration of crushed rock and gravel. This asphalt creates a bumpy surface that offers more traction. Many public roads are built with this thicker aggregate mixture, for safer driving and to reduce the need for salting icy or snowy roads in wintertime.
What causes asphalt damage?
One of the most common causes of asphalt damage is an oil leak from your vehicle, as motor oil will break down the petroleum used to create bitumen. When this happens, asphalt loses its adhesion and chips or holes then form.
Other common causes of asphalt damage include:
- Poor drainage. Standing water is absorbed by asphalt so that the material becomes soft and more prone to breakage.
- Heavy vehicles. Asphalt is poured to a certain thickness, and the thinner the pavement, the less weight it can manage. Driving or parking hefty cars over thin layers of asphalt can cause eventual craters in the material.
- Turning car wheels. Turning or twisting car wheels while the car is stationary can cause indentations in soft asphalt, leading to chips or craters in the material.
- Over time, sunlight and oxidation both break down the adhesion of bitumen, so that the material eventually becomes brittle and more likely to crack and chip.
How long should an asphalt driveway last?
A typical asphalt driveway might last 20 or 25 years, depending on how well you care for the material. Regular seal coating, as recommended by the installer, will protect the asphalt surface and prolong its life, and help to avoid everyday chips and cracks.
Note, too, that the original installation of the asphalt will affect its overall lifespan. A cheap, thin layer of rocks or gravel for the foundation of asphalt, or not pressing the new road into place correctly, can allow the blacktop to shift and settle so that cracks then form. Investing in a thicker base aggregate made of high-quality gravel can prolong the life of your asphalt driveway and keep its surface in good repair.
Should you patch, resurface, or replace the driveway?
Even if your home's asphalt driveway is severely damaged, you may not need to replace it, but can often have the material patched or resurfaced. Your options will depend on the driveway's age and the extent of the damage to its surface.
Over the years, consistent freeze-thaw cycles and the daily wear and tear suffered by an asphalt driveway will show up as small cracks, and patchy chunks that pull away from the surface of the asphalt. If these cracks or missing pieces are small, the deeper layers of the pavement are probably still durable and intact. You can have this damaged patched and have the driveway seal coated, for added protection.
Once those cracks are a few inches deep, a simple patch job won't keep the material strong enough for everyday use. You don't necessarily need to have the driveway torn up and replaced, but can often have the asphalt resurfaced, or a new layer of asphalt poured over the old and then rolled or pressed into place.
Whether or not you can have your current driveway resurfaced versus replaced will depend on the thickness of the asphalt, and the extent of its overall damage. After a few years, asphalt will start to degrade, so that it can't provide a strong enough foundation for additional layers. Trying to press a new coat of blacktop into such a degraded driveway would then be a waste of time and money.
Also, the foundation aggregate used to support asphalt can also only withstand so much weight. Adding too many layers of blacktop on top of this aggregate can result in a driveway that sinks, sags, or otherwise shifts out of place. Once the layers of your blacktop driveway reach a certain thickness, the asphalt will then need to be removed so that new aggregate and new asphalt can be installed.
If your property has drainage issues that have caused damage to the asphalt driveway, it can also be pointless to add a new layer of asphalt over the old! Your driveway may need to be torn out entirely so that your property can be graded, or so that a drainage system can be installed, to protect your new blacktop from this same water damage.
If your home's blacktop driveway is severely damaged, you may even want to consider having an entirely new type of asphalt driveway installed. If you live in a rainy climate, for example, a smoother asphalt might allow more water to run off the blacktop surface. Some asphalt mixtures are especially porous so that standing water will drain through the layers of blacktop, protecting its surface from water damage.
Should you install a concrete driveway?
Concrete has its advantages, but homeowners prefer asphalt for many reasons. If you do need to have your home's asphalt driveway torn out completely, note a few reasons why you might stick with asphalt as a replacement.
- Sound absorption. Porous blacktop absorbs sound waves so that an asphalt driveway can mean a quieter home exterior. This material can be especially crucial for those who live near busy roadways or noisy schools!
- As said, asphalt can be made with a rougher aggregate so that it has a very bumpy surface, providing added traction for driving and walking. Not only can this added traction be necessary when you're pulling your car in and out of the driveway, but consider if you have children who play on the home's asphalt, and who might suffer fewer slips and falls on a textured blacktop versus a slick concrete surface.
- Color and appearance. Concrete can be painted or stained so that your home's driveway provides some contrast to the exterior of your house, but this can make it difficult to repair cracked concrete, as you then need a patching compound that matches that color exactly. The dark color of blacktop provides a natural contrast to a home exterior, without requiring special paints, stains, or patching materials to match.
- The speed of installation. Concrete often takes many days, if not even a few weeks, to set and cure completely before you can drive on it. You may also need to keep a close eye on a newly poured or resurfaced concrete driveway so that no one vandalizes it before it sets. Blacktop, however, often requires only a day or two after installation before it's ready for use.
One of the most apparent advantages of asphalt over concrete is the cost of installation and repairs, as resurfacing blacktop is often much cheaper than repairing a concrete driveway. Choosing asphalt rather than concrete can then be the most long-term economic choice.
How to save money on asphalt resurfacing and replacement
Even though asphalt is typically more affordable than concrete, you may be wondering how to save money on its installation, especially if you need to have your old driveway torn out before having a new one installed. To ensure you're saving the most on your new blacktop driveway, note a few things to discuss with your paving contractor.
- Ask about using recycled material. Asphalt is entirely recyclable, and older pieces or sections of this material can usually be harvested and mixed in with new batches. Not only does this keep old asphalt out of landfills, but it can also be less costly than mixing up new blacktop with virgin materials. Ask your contractor about having asphalt made with recycled or reclaimed materials, to note if it would be cheaper for you.