Building restoration describes the process of the renewal and refurbishment of the fabric of a building. The phrase covers a wide span of activities, from the cleaning of the interior or exterior of a building  such as is currently underway at St Paul’s Cathedral in London  to the rebuilding of damaged or derelict buildings, such as the restoration of the Windsor Great Hall in Windsor Castle after a destructive fire in 1992. The 1985–1989 removal of 38 layers of paint and the cleaning and repair of the exterior sandstone walls of the White House in the USA are an example of building restoration. Buildings are structures which have, from time to time, particular purposes. They require ongoing maintenance to prevent them falling into disrepair as a result of the ravages of time and use. Building restoration can be thought of as that set of activities which are greater than year-to-year maintenance, but which by retaining the building are less than a demolition and the construction of a new building. The scope of restoration depends upon the need, and other circumstances, such as the status of the building, and the affordability of the work required. There are three main types of restoration:
Not all building restoration seeks to follow the original design of the building. It is reasonably commonplace for the shell of a building  its external walls  to be retained whilst an entirely new building is constructed within. This approach is also referred to as adaptive reuse. Although techniques of restoration are improving, the action of cleaning or repairing buildings can, with hindsight, be seen to cause problems that at the time were unforeseen. A good example is the unrestrained use of sandblasting to clean smog deposits from soft-stoned buildings  a technique employed in the UK in the 1960s and 1970s  which has damaged the external faces of stonework to the extent that in some cases, later, the stonework has needed to be replaced. Contemporary building codes recognise such problems, and (it is to be hoped) mitigate poor outcomes.
From Wikipedia, the free encyclopedia : Interior cleaning of buildings |