Having a paved driveway or parking lot has many benefits over gravel, dirt, and even concrete. It's neater, looks better, and doesn't turn to mud when it rains. However, a paved asphalt lot or driveway comes with maintenance requirements of its own.
Asphalt expands and contracts with the temperature and weather conditions. This improves durability, but over time, it's important to make sure the asphalt is still holding strong.
Repaving vs. Seal Coating
There are two common ways to maintain aging asphalt pavement. Many people opt for repavement, but seal coating is also a good option. Each has its own advantages and disadvantages.
Repaving your asphalt driveway or lot entails putting new asphalt down. It can either be laid on top of the existing driveway, or the current asphalt can be torn up and replaced. If the asphalt has undergone major damage, such as large cracks, or is deteriorating from underneath due to groundwater erosion, repaving might be the best course of action. Putting it off might only make the problem worse.
The cost to rip up an old driveway, remove the debris, and lay down a new one is usually several thousand dollars, with some jobs costing up to $5,000, depending on the scope of work and the home or business location.
If your driveway is in fairly decent shape, and you are performing simple preventative tasks to keep it strong for many more years, repaving it completely probably isn't necessary. Repaving is a long and expensive process and only truly needs to be pursued when the driveway really is at the end of its life. A good rule of thumb is if one-quarter of the driveway or more needs to be repaired, repaving is the way to go. But if less than that is crumbling, a seal coat would be sufficient.
Putting a seal on your asphalt driveway will help it resist water damage and can double its lifespan. It will also protect against oil spills and pothole formation, and helps ice and snow melt faster. Plus, it shields the driveway from UV rays, which can cause the asphalt to become brittle.
In addition to these benefits, seal coating is typically a much less expensive process than repaving. It generally costs a few hundred dollars. In 2016, the highest price was about $1,000 and the average homeowner paid less than $400 to seal coat their driveways. Every new asphalt driveway or parking lot should be seal coated, but the process must be done at least 90 days after the asphalt was laid. The optimal timeframe is between one and two years after the driveway is laid.
Types of Asphalt
It can be difficult to tell the difference between one paved lot and another. But when choosing an asphalt type for your driveway or parking lot, there are a range of options.
Hot Mix Asphalt (HMA)
HMA is the most common type used for driveways. Numerous benefits are associated with this style, including:
- High durability
- Low maintenance
- Polished look
- Resistance to salt, commonly used to prevent ice formation during the winter
- Able to withstand multiple freezes and thaws
- Easy to repair when needed
Perpetual pavement is generally used for roads and consists of three layers:
- The bottom layer is strong, flexible and resists deterioration. Either extra-thick or highly flexible HMA is typically used for this layer to improve durability. It's usually between 3 and 4 inches thick.
- The middle layer is strong and sturdy, as it will support the weight of the cars. Coarse aggregates combined with a binder are generally used to add durability and rut resistance. This layer is typically between 4 and 7 inches thick.
- The top layer is meant to be the driving surface. It's usually a high-quality HMA that's 1.5 to 3 inches thick. This layer is designed to combat rutting and stress cracking.
Roads made of perpetual pavement have their top layer torn up and replaced every few years, but the bottom and middle layers are meant to be permanent.
Quiet or Stone Matrix Asphalt
Stone matrix asphalt has several qualities that make it perfect for highways with heavy traffic volume. Using this type can reduce noise pollution by as much as 50 percent, which makes it ideal for travelers on long road trips or anyone who lives near a highway. It's also highly durable and very resistant to rutting. However, it's also significantly more expensive than other options, so it isn't often used for driveways, parking lots, or even smaller roads.
Porous asphalt is usually laid on top of a recharge bed that rainwater can drain into through the pavement. It's a common choice in parking lots to prevent surface flooding and can also help improve groundwater quality.
Common Uses of Asphalt
Asphalt is highly versatile, very durable and fairly affordable for many people. It's primarily used for road surfaces; 94 percent of U.S. roads are made of asphalt. Other uses include:
- Parking lots
- Tennis or basketball courts
- Airport runways
Questions to Ask When Choosing a Paving Contractor
While your driveway or parking lot certainly isn't what makes you or your home or business great, it is a contributing factor to people's first impressions. Bad pavement jobs can result in pooling rainwater and premature cracking, so you need to choose a paving contractor who can deliver a durable, professional-looking surface. Before deciding on a contractor, hold a few interviews to determine which company is best for your job.
Are You Insured?
Any time you hire a contractor to complete a project at your home, you should double-check to make sure the company is insured. Liability and worker's compensation are good starts, but having an umbrella policy and auto liability are also ideal.
Is Your Asphalt Recycled?
Most asphalt is partially made of recycled material. Some people prefer recycled asphalt because it's more environmentally friendly than new asphalt. However, too much older material in your new driveway can make it look worn down and decrease its lifespan. Be sure to inquire about the ratio of new to recycled asphalt.
What Type of Equipment Do You Use?
Asphalt needs to be laid quickly and efficiently to ensure it looks nice. Asphalt that begins to cool before the rest of the job is done will end up sloppy. If your contractor uses outdated equipment that is prone to breakdowns, you're taking the risk that this situation will occur.
If the contractor responds to this question by saying he or she can pave an asphalt driveway by hand, consider looking for another contractor. He or she might be highly skilled at hand-paving, but a machine will generally do a better job that will look nicer and last longer.
How Much Will It Cost?
Of course, you'll want to get a quote during your contractor interviews. One red flag is being asked for a down payment. The typical asphalt paving job shouldn't require a down payment.
If the quote sounds too high, ask what is included. The size of the job will make a difference, as well as necessary materials. If your driveway or parking lot needs to be leveled out or if there are drainage issues present, your quote might begin to creep higher. Talk about the grade of asphalt and any challenges your job requires - these could increase the cost.
On the other hand, if a quote seems unrealistically low, find out why. Perhaps their equipment is outdated or their asphalt is low quality. Worse is the possibility that there are hidden fees you didn't discuss during the initial conversation.
Do You Have References I Can Call?
Speaking to people who have worked with this contractor before is one of the best ways to get a feel for how they work with clients. You can also search online to see if anyone has reviewed the company on sites like YP.com.
Additionally, ask if there are any nearby examples of the company's work you can see. Perhaps they've done parking lots you drive by every day.
How Many People Will Work on My Project?
Ideally, your contractor will have a crew of between five and eight people. Too few will make the job challenging, which could result in a poorly laid driveway.
Common Issues and Hazards
When asphalt gets old, or if the wrong type of asphalt was used for a particular job, certain types of defects can begin to show.
Alligator Cracks and Potholes
These are scaly-looking cracks that run throughout a portion of a road. They are caused when the asphalt wasn't provided enough support or drainage. Over time, they can deteriorate until they become potholes.
Prevent alligator cracks by making sure the base layer is strong enough. If you begin to notice alligator cracks or potholes, only a full-depth patch can remedy them.
Longitudinal, Transverse, and Joint Reflection Cracks
Joints are usually the weakest part of a paving job, and inadequate joint construction can eventually lead to cracks.
Longitudinal cracks are parallel to the road's centerline or the direction the driveway or parking lot was paved. They are usually caused by poor joint construction or simply aging pavement.
Transverse cracks run perpendicular to the road's centerline, and can be caused by poor joint construction as well. Seasonal or daily temperature changes can also contribute to transverse cracks.
Joint reflection cracks occur on asphalt surfaces that are laid over concrete surfaces.
Bird Baths, Edge Cracks, and Rutting
These issues are usually seen on the sides of roads. Bird baths, or depressions, are caused when the pavement isn't as deep in one area, or the land on which the road was laid is uneven. A slight depression can be fixed with another layer of asphalt.
Edge cracks are generally caused by weak edges. When there isn't enough support at the edge, the road will begin to stress and crack over time.
Rutting occurs in the wheel tracks of a road and is generally seen when the asphalt isn't thick enough to support traffic.