The front door is the focus of the façade of most old buildings and, as with internal doors, including historic cupboard doors, a clue that assists with dating a building or later alterations. The diversity and hierarchy of door designs in different parts of a building provide added interest, as does evidence of changes to individual doors.
Doors developed from those of simple construction typical of cottages, with boards fixed vertically to horizontal timber ledges, perhaps with diagonal braces, to the more formal panelled forms characteristic of the 18th and 19th centuries. Whatever the type, it is important that old doors and their associated features are retained wherever possible.