TarmacadamTarmac, short for tarmacadam, involves the coating of layered crushed stone with tar in order to create a strong, durable surface. The addition of a top coat will improve water resistance and grip, as well as adding a more aesthetic quality to the material.
Unfortunately tarmacadam is rather prone to damage from petrol or diesel spills, and today tarmac has almost entirely been replaced by the use of bitmac.
Bitmac replaces the tar from the tarmacadam process with bitumen, and this newer surface is actually even more similar to asphalt than tarmac. Asphalt is made by combining a blend of aggregates with bitumen to bond them together, although the major difference between this and bitmac is that bitmac contains much more sand and filler.
AsphaltAsphalt can be quite cheap when used over a large area, hence why it is often used for road surfaces, but for a small surface it can be an expensive option. Asphalt is also much harder wearing than bitmac or tarmac, but at the cost of being less resistant to scuffing from car tyres. However, asphalt is not as affected by extreme weather as much as tarmac, and also requires less maintenance over time.
Modern asphalts are also more sustainable and environmentally friendly, as old surfaces can be reclaimed and reused in a new setting with relative ease. But it is important to note that when the term asphalt driveway is used it may be referring to one comprised of asphalt concrete, which is an entirely different type of surface.
Asphalt concrete surfaces mix asphaltic cement with finer aggregates such as sand or grit. These surfaces can last much longer than regular asphalt driveways, but they come at a much higher cost, require much trickier repairs, and they are far more susceptible to damage from temperature fluctuations.