The primary use of asphalt is in road construction, where it is used as the glue or binder mixed with
aggregate particles to create
asphalt concrete. Its other main uses are for
bituminous waterproofing products, including production of
roofing felt and for sealing flat roofs.
The terms
asphalt and
bitumen are often used interchangeably to mean both natural and manufactured forms of the substance. In
American English, asphalt (or asphalt cement) is the carefully refined residue from the
distillation process of selected crude oils. Outside the United States, the product is often called bitumen. Natural deposits terminology also sometimes uses the word bitumen, such as at the
La Brea Tar Pits.
Naturally occurring asphalt is sometimes specified by the term "crude bitumen"; its viscosity is similar to that of cold
molasses. whilst the material obtained from the
fractional distillation of
crude oil [boiling at 525 °C (977 °F)] is sometimes referred to as "refined bitumen".