Refurbishment is a perennial activity. It has increased as large numbers of buildings have become derelict or obsolete because of the decline of traditional industries. Building stock is a valuable resource and heritage but, like any resource, it has a finite life. This life can be extended and the value of a building restored, and even enhanced, by carefully-considered and well-implemented refurbishment. A key criterion is the fact that most buildings under consideration for refurbishment were designed in eras when energy use was not an issue. Therefore imaginative engineering is necessary to bring them into line with current financial and environmental requirements.