PPS 6 Planning Archaeology and the Built Heritage·Page 49·C6
External Appearance and Special Interest in Listing
External appearance is key in listing selection, but buildings important for technological innovation or historical significance may lack visual appeal and can still qualify for listing.
The external appearance of a building (both its intrinsic architectural merit and group value) is a key element in selecting buildings for listing, but the special interest of the building may not always be reflected in obvious visual quality. Buildings which are important for reasons of technological innovation, or as illustrating particular aspects of social or economic history, may well have little visual appeal.
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