What is the difference between tarmac and asphalt?

When it comes to roads and driveways, the terms "tarmac" and "asphalt" are often used interchangeably. After all, they both play crucial roles in surfacing and paving. However, delve a little deeper, and you'll discover that there are significant differences between the two materials. If you’re considering getting your driveway resurfaced and are wondering whether to go for tarmac or asphalt, we’re here to explain the differences and help you decide which type of surfacing is best for you.

Tarmac vs asphalt - the composition

Let's start with asphalt. Asphalt, also known as bitumen, is a sticky, black, and highly viscous liquid or semi-solid form of petroleum. It's a composite material commonly used in road construction and surfacing projects. The primary components of asphalt include aggregates (such as stone, sand, or gravel) bound together by bitumen. This combination creates a durable and flexible surface that can withstand heavy traffic and varying weather conditions. On the other hand, tarmac is a specific type of road surface made from a mixture of tar and crushed stone or gravel. It's important to note that "tarmac" is actually a colloquial term derived from "tarmacadam," which itself is a portmanteau of "tar" and "macadam." Originally, tarmac referred to roads constructed using layers of crushed stone bound with tar. However, modern tarmac surfaces may incorporate asphalt or other bituminous materials in their composition.

The Construction Process

The construction processes for asphalt and tarmac surfaces differ slightly, reflecting their distinct compositions. Asphalt surfaces are typically constructed in layers. The process begins with the preparation of the underlying surface, followed by the application of a base layer of asphalt concrete, often referred to as "base course." This is followed by the installation of a binder layer and finally a surface layer, known as the "wearing course," which provides the smooth, finished surface. In contrast, tarmac surfaces are constructed using a process known as macadamisation. This involves applying layers of crushed stone or gravel onto a prepared sub-base, which is then bound together using tar or bitumen. The surface is compacted and rolled to create a smooth finish. While the basic principles of both construction methods are similar, the specific materials and techniques used vary.

Tarmac vs asphalt - Durability and Performance

When it comes to durability and performance, both asphalt and tarmac offer distinct advantages. Asphalt surfaces are renowned for their resilience and ability to withstand heavy loads and high traffic volumes. The flexibility of asphalt allows it to adapt to changes in temperature and prevent cracking and deformation over time. Additionally, asphalt surfaces can be easily repaired and maintained, extending their lifespan. Tarmac surfaces, while also durable, may be more prone to wear and tear over time, particularly in areas with extreme weather conditions. The use of tar as a binding agent in tarmac can make it susceptible to softening in high temperatures and cracking in freezing conditions. However, with proper maintenance and occasional resurfacing, tarmac surfaces can remain functional and cost-effective for many years.

In conclusion…

In conclusion, while tarmac and asphalt are often used interchangeably to describe road surfaces, they are distinct materials with unique compositions, construction processes, and performance characteristics. Asphalt, made from bitumen and aggregates, offers durability, flexibility, and ease of maintenance. Tarmac, on the other hand, incorporates tar and crushed stone or gravel, providing a solid yet slightly less resilient surface. Understanding the differences between tarmac and asphalt is essential for making informed decisions in road construction and surfacing projects. By selecting the most suitable material based on factors such as traffic volume, climate, and budget, engineers and contractors can ensure the longevity and effectiveness of their infrastructure projects.

Premier Surfacing: how we can help

With over 20 years of experience in the surfacing and driveway installation industry, our skilled professionals bring expertise and precision to every project. We understand the nuances of each material and tailor our services to meet your specific requirements. If you have any questions about whether to choose tarmac or asphalt for your surfacing project, we can help. We source high-quality materials to ensure the longevity and durability of your driveway. Our commitment to using premium materials contributes to the overall quality and performance of our installations.