If it is better to use concrete vs asphalt roads is not always so easy to determine. While both concrete and asphalt are popular materials for roads, there are a few pros and cons to each that can make one a far better material for the job at hand than the other.
Concrete roads are more environmentally friendly and have more longevity compared to asphalt roads, though asphalt is more cost-effective and can be a safer alternative to asphalt in areas that get a lot of snow.
Read on as we go through the pros and cons of concrete vs asphalt roads.
What Are Concrete Roads?
Most concrete roads are a combination of aggregates (gravel, sand, and rock), water, and cement. Cement is in the mix as a binding agent to hold the aggregate together. The stiff, unforgiving slabs of concrete form when the mixture dries. Construction crews will often try to refrain from making the surfaces of concrete roads perfectly smooth, as perfectly smooth concrete is often more prone to breakage.
To reinforce concrete, construction crews will often use steel bars.
The Pros of Concrete Roads
Longer Lifespan
When it comes to concrete vs asphalt roads, concrete roads have a much longer lifespan. In fact, many concrete roads can last up to 20 to 40 years with minimal maintenance; it is around two to four times the average lifespan of asphalt roads. This is one of the many reasons people also use concrete to make catch basins, especially in areas with heavy rainfall.
Better For Highways
Our national highways are under the constant pressure of large freight trucks that travel over them every day. Concrete handles weight much better than asphalt, meaning it is less prone to rutting or dips. If you’re planning on paving roads where there will be a high volume of large trucks, concrete is the better material.
Of course, the one major downside to using concrete on long stretches of highway is that it can get expensive very fast, which is something to consider in any road-building project.
Safer For Motorists
Thanks to the longevity of concrete roads and the strength to hold more weight without dips forming, there is a smaller chance of potholes forming. Not only does this make it safer for motorists, but it also helps traffic to flow much smoother too.
Better Fuel Efficiency
According to a number of studies of concrete roads vs asphalt roads over the past decade, concrete roads can reduce CO2 emissions and increase driver fuel efficiency. It is said that drivers get anywhere from 1-7% better fuel efficiency when driving on concrete roads compared to asphalt roads. This is because concrete roads don’t fold as much under the weight of vehicles.
More Environmentally Friendly
In general, the production of concrete roads is more environmentally friendly than that of asphalt roads. Essentially, concrete uses less energy during the construction process with fewer vehicles and passes, giving the construction process a small carbon footprint.
It is also worth noting that concrete does not produce any sort of toxic runoff like asphalt does, meaning it is not a threat to local waterways. With its unique permeability, concrete allows rainwater to pass through it so that groundwater can be replenished, just as grass would allow water to pass through.
Of course, neither of these options is sustainable options, though that does not mean one isn’t better for the environment than the other.
Saving On Resources
Concrete, which is made from cement, is produced from limestone. Limestone is readily available and a very abundant resource that does not need to be imported in.
No Oil Damage
Unlike asphalt roads, concrete roads do not suffer damage from oil leaks.
Better For Colder Temperatures
Concrete is a better choice for areas with colder temperatures, as it is more resistant to the freeze-thaw cycle. This also makes it a much safer choice for drivers in snowy or icy conditions.
Recyclable
Many consider concrete to be recyclable, as old slabs of concrete can be ground up and used as gravel in other projects, such as gravel driveways.
Coloring and Stamping
One of the biggest aesthetic advantages of concrete is that it can be stamped and colored much easier than asphalt. You’ve likely been in urban settings where the concrete is colored in certain places to section off bike lanes or to promote safer crosswalks. The number of aesthetic possibilities is much greater with concrete than with asphalt.
Light Color
One of the main reasons you’ll often see concrete roadways in hot areas is that the lighter color is more reflective than asphalt. This means that it reflects the radiation from the sun instead of absorbing and storing it as asphalt does.
With a cooler surface, concrete can help surrounding buildings, meaning businesses and homes, cut back on their energy costs. It doesn’t get as hot in urban settings with concrete compared to those with asphalt, either.
Cons of Concrete Roads
Difficult Repairs
Repairing concrete roads if they do get damaged can be an arduous process. It is impossible to patch holes and cracks on concrete roads vs asphalt roads. Instead, to repair concrete, the entire slab must be replaced.
Costly
Concrete costs a lot more than asphalt, both in terms of the construction process and the potential repair process.
Bumpy Rides
Concrete slabs can sit at different levels, causing rides to be bumpier than asphalt. It is also often the case that drivers can feel the expansion joints in the road when driving on concrete, especially if they don’t have newer cars with high-quality suspension.
More Road Noise
During the construction process, the texture is brushed onto the concrete’s surface. Beyond drivers feeling the rhythmic bump of each suspension joint they pass over, it is also often the case that these roads are incredibly noisy.
Less Grip
Compared to asphalt roads, concrete roads don’t offer that much grip. When roads get extremely wet, it becomes far more likely that vehicles lose traction quickly. It is also the case that water does not evaporate as fast, nor does snow melt as fast, as concrete has a much lower heat absorption rate than asphalt.
High Reflectivity
If you’ve ever driven on a long asphalt road on a very hot, sunny day, you’ve probably noticed the high reflectivity characteristic. Driving on asphalt roads in this kind of heat and sunlight for a long time can be a major strain on the eyes.
Non-Absorbant
While asphalt has a great way of absorbing spills, such as oils, chemicals, and other pollutants, concrete does not.
Long Cure Times
After it is poured, concrete typically has to sit for seven days before it is cured. Of course, there are high-early-strength varieties of concrete too, which can cure in a day to three days, though these are much more expensive. If you’re looking to get a job done quickly, asphalt is a much better choice.
When To Use Concrete Roads
While concrete roads can be used in a number of different projects, they are best for:
- New construction
- Urban road expansion
- Build new roads in urban regions
- Underground utility repair
It is also worth noting that concrete is a 100% recyclable material. It is pretty common for construction companies to break concrete down and use it to build new bridges and roads or use it for other construction projects entirely.
Because concrete does not require as much maintenance or repairs, there are fewer costs to maintain it, including machinery costs, fuel costs, labor costs, etc.
What Are Asphalt Roads?
Asphalt roads are often made up of aggregates (gravel, sand, and crushed rock), filler, and binder (bitumen). Bitumen is a very different kind of binding agent than cement, as it is a dark and sticky substance that is derived from crude oil.
When roads are built using asphalt, fine aggregate is mixed with bitumen while heated up before it is poured onto a bed of large aggregate. Once it is laid down, it is pressed into place using a steamroller.
The beauty of asphalt is that it is ready to be driven on once it cools down to the surrounding air temperature. It is also much more flexible than concrete, allowing it to better mold to the imperfections of the ground underneath.
Pros of Asphalt Roads
Cost-Effective
When it comes to concrete vs asphalt roads, the materials for asphalt roads cost less than they do for concrete. Plus, since the construction process moves a lot faster for asphalt roads, it requires less time and energy to build, meaning less spent on labor and machinery.
Easy To Repair
Unlike concrete, it is possible to repair asphalt in patches. If there is a small crack or dip somewhere in the road, filling it up and patching it over is quite easy.
Better Traction
There are many people who deal with dynamic driving situations, especially those who live in hilly areas or regions that have inclement weather. Compared to concrete roads, asphalt roads offer far more traction and skid resistance, making them a safer option in many ways.
Less Noise
While concrete roads can be very noisy to drive on, asphalt roads are generally quiet. This is especially true for brand-new asphalt roads.
Better Heat Absorption
Though asphalt can get really hot, the good thing is that it has excellent heat absorption for those who live in snowy areas. After a long bout of inclement weather, snow and ice will melt much faster off the road than concrete. Rainwater will also evaporate much faster on asphalt.
Recyclable
Many consider asphalt recyclable as well, as you can melt asphalt down and re-use it to surface new roads.
Cons of Asphalt Roads
Shorter Lifespan
Asphalt roads have a much shorter lifespan than concrete roads. On average, asphalt roads last around ten years. Maintaining an asphalt road requires it to be re-laid and repaired on a more regular basis.
Easily Damaged
When heavier weather approaches, asphalt tends to take on more damage. In regions with heavy snowfall or monsoons, this can be a huge problem. Oil leaks can also have an impact on damage when asphalt absorbs it, as it can weaken the binding agent. When the binding agent is weakened, the roads can soften, leaving them open to further damage.
Not Great For Certain Types of Roadways
Because asphalt is prone to cracking and breaking under stress, it is not the best choice for high-turning points or stopping points. Of course, to reduce rutting, it is possible to mix asphalt with harder oil. However, this can also make it more brittle, which can lead to the asphalt breaking when temperatures get low.
Less Environmentally Friendly
When asphalt is melted during the construction stage, it can emit greenhouse gases. Compared to concrete roads, building asphalt roads can cause far more pollution.
More Prone To Freeze Damage
When winters roll around and the freeze-thaw cycles begin, it can wreak havoc on asphalt roads. These kinds of roads become far more brittle in extremely cold temperatures due to their less flexible makeup.
Uses More Natural Resources
Asphalt is made from bitumen, which is produced from imported petroleum. Every day, the reserve of bitumen is reduced more and more, meaning it will eventually cost us more to import and use for major roadways.
When To Use Asphalt Roads
- New roads in rural areas
- Low-volume roads
- Jobs that require cost-efficiency
Final Thoughts – Concrete Vs Asphalt Roads – Which One Is Best?
There isn’t a one-size-fits-all answer for which of these materials is better for building roads. It’s crucial to consider the specifications of your project when trying to choose the better material.
Concrete is a more sustainable option that promotes better fuel efficiency and longevity. But it can also be expensive and difficult to repair. It is also worth noting that many governments are shifting to the use of concrete roads thanks to the reduced chance of potholes and added longevity.
On the other hand, asphalt can be more cost-effective and safer for drivers due to its skid-resistant nature, though it is less environmentally friendly and more prone to damage.
Consider the parameters of your road-building project and the pros and cons of each when making your next decision.