Asphalt and tarmac may have been used interchangeably when it comes to paving roads, driveways or airport runways. However, are they identical? The yes or no is not as simple as it can be and the variations can guide homeowners, contractors and drivers to make informed decisions regarding paving materials.
What Is Asphalt?
One of the common paving materials is asphalt. It is produced by mixing aggregates (such as sand, gravel, and crushed stone) and a binding material known as bitumen, a sticky, black and viscous liquid of crude oil.
Key Features of Asphalt
Strong and elastic: Asphalt is not able to crack easily due to heavy traffic and temperature changes.
Smooth surface: It has a smooth texture which makes it suitable in highways, roads and driveways.
Fast installation: The asphalt may be installed and put into use more quickly than various other paving materials.
Cost-effective: Tend to be inexpensive compared to concrete or tarmac in large scale construction.
Asphalt is the commonest road construction material used due to its durability, versatility, and ease of access.
What Is Tarmac?
Tarmac also known as tarmacadam is a paving material that was initially invented in the early 20th century by the British engineer John Loudon McAdam. Tarmac is produced as a mixture of tar, crushed stone or aggregate, rather than bitumen.
Key Features of Tarmac
Smooth surface: Tarmac is also smooth and suitable in vehicle travel.
Powerful adhesive: The tar is used to ensure that the stones are bonded and the tar is more resistant to water penetration.
Less flexible as asphalt: Tarmac may crack when subjected to heavy loads or extreme changes of temperature.
Less common: Tarmac is not commonly used on roadways or driveways in modern times, but it is still used on occasion on airport runways or historic locations.
It is necessary to mention that in normal speech, the word tarmac is commonly used to mean any paved area, even asphalt. This confuses a lot of individuals.
Asphalt vs. Tarmac: Key Differences
Although asphalt and tarmac might be similar, they differ greatly in terms of composition and performance.
Let’s break it down:
| Feature | Asphalt | Tarmac |
| Binder | Bitumen (oil-based) | Tar (coal-derived) |
| Flexibility | High, handles expansion & contraction | Low, prone to cracking under stress |
| Typical Use in U.S. | Roads, driveways, parking lots | Rare, sometimes airport runways |
| Cost | Generally cheaper | Generally more expensive |
| Appearance | Smooth, black | Slightly rougher, darker brown-black |
The largest distinction is the binder: asphalt -bitumen and tarmac -tar. This influences the durability, flexibility, and even impacts on the environment.
Why Asphalt Is More Common
Asphalt dominates road construction; there are several reasons for this:
Accessibility to raw materials: Bitumen is simpler to manufacture and obtain in the U.S. as compared to tar.
Climate factor: The flexibility of asphalt enables it to absorb the hot and cold climates witnessed in most states in the U.S.
Cost-effectiveness: Asphalt is cheaper to manufacture and install as compared to tarmac.
Maintenance: The tarmac is difficult to patch or resurface, in contrast to asphalt, which is a key factor when dealing with high-traffic roads.
Consequently, Americans might have heard of tarmac, but they hardly see it beyond an airport or any history book.
What most people believe about Asphalt and Tarmac:
Homeowners and drivers can be confused by several myths and misconceptions about these materials that are present.
Myth 1: Tarmac and Asphalt are the same.
As we have mentioned, the two materials have varying composition and performance. Although they might sound interchangeable, it would be technically wrong to refer to asphalt as tarmac in the U.S.
Myth 2: Tarmac is better than Asphalt.
Tarmac is not susceptible to cracking as asphalt because it is less flexible, although it is durable. The capacity of asphalt to contract and expand makes it more applicable to most of the contemporary applications.
Myth 3: Asphalt Is Road Only.
Asphalt is in fact quite versatile. It can be used for:
- Driveways
- Parking lots
- Sports courts
- Airport runways
- Walkways and paths
- Environmental Considerations
Asphalt and tarmac both have environmental effects but asphalt has a superiority in the area of sustainability. Recycled materials, including reclaimed asphalt pavement (RAP) or recycled plastics, can be used in modern asphalt and waste can be minimized, which conserves resources.
Tarmac on the other hand employs tar which is a by-product of coal. Production of tar creates more greenhouse gases and pollution than bitumen, and thus, tarmac is a less environmentally-friendly option.
Asphalt versus Tarmac:
When you are thinking about a paving project in the U.S., a simple guideline is as follows:
In the case of driveways, roads and parking lots: Asphalt is the most suitable because it is cost effective, durable and is available.
In specialized projects such as historical restorations or certain surfaces of airports: Tarmac can still be applied, but it is not common.
When one in the U.S. mentions the tarmac driveway, they in most occasions refer to asphalt.
Maintenance Tips
Asphalt Maintenance
- Sealcoating: A sealcoat is used to cover asphalt after every three to four years to prevent water, UV rays, and wear.
- Crack filling: Small cracks are to be filled immediately in order to avoid their expansion.
- Pothole repair: Rapid Pothole repair prolongs the life of asphalt surfaces.
Tarmac Maintenance
- Frequent check: Detect cracks and erosion which may be caused by water or heavy vehicles.
- Resurfacing: Tarmac can be resurfaced after some time to ensure that it is structurally sound.
- Do not expose tar to heat: Tar may become soft, and thus cause damage.
Correct care can add decades to the life of either of the materials, which will save money in the long run.