PPS 6 Planning Archaeology and the Built Heritage·Page 65·E38
Protection of Listed Buildings during Building Works
Protection measures are necessary during alterations to listed buildings to prevent damage. These range from dust sheets and sealing doors to specialized protection for vulnerable features such as stairs.
Protection is always necessary to a greater or lesser extent when work to a listed building is underway. This may be as little as providing a few dust sheets and sealing communicating doors to prevent dust and dirt from invading the whole building. Especially vulnerable features will need greater protection. Stairs are one element commonly damaged and abused during building work.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/PPS 6 - Planning Archaeology and the Built Heritage.pdf