Tarmac vs Asphalt: The Key Differences and Uses
Estimated reading time 5 minutes
Tarmac and asphalt are often framed as the same thing, but there are some key distinctions between the two that many may overlook. In this blog, we explore those as well as potential costs, advantages, uses and more. In short:
- Asphalt: Aggregate + bitumen
- Tarmac: Aggregate + tar
What many people may call a tarmac driveway or path today is almost always an asphalt/bitmac mix because tar has largely been replaced by bitumen.
What is asphalt?
Asphalt is a mixture of aggregates bound together with bitumen. It is the standard surfacing material for UK roads, with more than 95% of the road network using some form of asphalt. Known for its strength, flexibility and ease of installation, it is often chosen for motorways, car parks, driveways, playgrounds and more.
You’ll often see asphalt used as an umbrella term for several different mixes, each designed for a specific job, but they all share the same composition: aggregate, held together by a bitumen binder.
What is tarmac?
Tarmac, short for tarmacadam, is a surfacing material made from crushed stone bound with tar.
Tarmac is often referred to as the surface material for driveways, paths, race tracks and more, but there is a little confusion here. True tarmac is now rarely used. It’s been replaced in most cases with bitumen, and the material most people may refer to as tarmac is, in fact, asphalt, or bitmac. The labelling has remained the same despite the material beneath it having changed.
Tarmac vs asphalt: What’s the difference?
The core differences between the two lie in the binder. Asphalt is bound with bitumen, while true tarmac is bound with tar. That distinction is what drives differences in durability, finish, and perhaps importantly, cost.
As the two names often become muddled and modern tarmac is normally bitmac, the comparison is normally more between a domestic-grade surface and a harder-wearing engineered asphalt.
Our table below outlines key differences:
| Asphalt | Tarmac (tarmacadam) | |
| Binder | Bitumen | Tar |
| Durability & lifespan | Higher. Long-lasting under heavy use | Lower. Better suited to light use |
| Surface & drainage | Smoother finish, porous mixes available | Coarser finish, more prone to surface water |
| Best used for | Roads, car parks, heavy-traffic commercial surfaces | Domestic driveways, paths and light-use areas |
Essentially, if you need a surface that supports heavy vehicles or frequent traffic, such as a car park or a commercial yard, asphalt is almost always the best choice.
If your surface only encounters light or infrequent traffic, a tarmac-style surface can be a cost-effective option.
Because the binder affects how the surface copes with spills and standing water, the right choice depends on how much the surface will be used as well as the upfront price.
Both asphalt and tarmac are bitumen or tar-based, so both can be damaged by petrol, diesel and oil. Spills dissolve the binder and need prompt cleaning. Older tar-bound surfaces are particularly vulnerable, which is one of the reasons bitumen largely replaced tar.
How much do tarmac and asphalt cost?
The cost for having tarmac or asphalt surfaces laid depends on more than just the surface material chosen. Depth, sub-base condition and the area covered are perhaps more determining factors than the material itself.
The factors that most affect the final cost of your installation include:
- Area and shape: Larger, simpler areas can cost less per square metre than small, awkward ones.
- Sub-base condition: A failed or missing base has to be excavated and rebuilt before surfacing. This can significantly add to the cost.
- Traffic-loading: A surface that needs to withstand HGVs or continuous traffic will need a deeper and stronger construction than a domestic driveway.
- Finish: Certain finishes, such as coloured asphalt, will carry a premium over the more standard black surfacing.
It is also worth remembering how much difference in price there can be between a commercial and a domestic project. A small driveway, for example, is a self-contained job that could be completed in a short space of time. A car park, access road or commercial yard, on the other hand, is a larger project that often includes phased work to keep the site running. For that reason, the best way to get an idea of the estimated expense is to book a site survey with Tidey and Webb. That way, you’ll have a clear indication of cost, timelines and the level of work required.
Which should you choose?
The right surface will depend on what it has to carry. A domestic driveway or a light-use path will benefit from a standard tarmac-style or asphalt surface. However, if the surface has to endure frequent heavy loads, the considerations change considerably:
- Driveways and paths: Light use, appearance and cost are the main drivers.
- Roads and estate access: Need a durable, flexible surface that copes with repeated traffic and can be maintained in sections.
- Car parks and commercial yards: Require stronger construction, proper drainage and often, line marking and a phased installation.
- Adopted-standard and heavy-duty work: Must meet specific engineering and highway requirements, which dictate the material and the build-up beneath it.
This is where the choice stops being about the name of the material and becomes more of a question about engineering, drainage and the sub-base. For commercial surfacing and civil projects in particular, getting that specification right determines whether a surface lasts or fails early.
Still unsure what surface type is best for you?
Whether you are resurfacing a driveway or planning a commercial car park, the right material and construction depend on how the surface will be used. Tidey and Webb are specialist surfacing and civil engineering contractors working across Sussex, Surrey and Kent, with more than 40 years of experience laying durable surfaces for both domestic and commercial clients. Contact us today to talk through your project or book a free site survey.
