PPS 6 Planning Archaeology and the Built Heritage·Page 57·E3(1)
Minimum Interference Principle
The first guiding principle for conserving listed buildings is to minimize interference with original fabric, maximizing retention of historic material as every element provides evidence of the building's history and past.
The first principle is that of minimum interference and every scheme should therefore aim to conserve a maximum of the original fabric of the listed building, whether or not it will be seen. An historic building is like a coded book and every inch of it speaks to us about its past, its owners, its builders, fashions, customs, times of plenty and times of scarcity. Each piece of its fabric lost is like tearing a page out of this history book.
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