PPS 6 Planning Archaeology and the Built Heritage·Page 27·6.14
Alterations to Buildings in Architectural Groups
Where a listed building forms part of an architectural group such as a terrace, even minor external alterations including painting or stone cleaning may disrupt the architectural unity of the group.
Where a building forms part of an architectural group, for example as part of a terrace, then it may not be possible to make even minor external alterations without disrupting the architectural unity of the group. Even painting or stone cleaning of only one unit in a terrace can have this effect.
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