Asbestos is a naturally occurring mineral that was widely used in construction materials throughout the 20th century. It was prized for its heat-resistant and fire-proof properties, and was commonly used in wall and ceiling insulation, roofing materials, and pipe insulation. However, it was later discovered that asbestos exposure can cause serious health problems, including lung cancer, mesothelioma, and asbestosis.

While asbestos is no longer used in modern construction, many older buildings still contain asbestos materials. This is why it's important to have an asbestos survey carried out before any refurbishment or demolition work takes place.