01
Map the interaction
Show the contractor the lower roof and discuss how tools, materials, and removed components will be handled. Ask how the slate will be protected and whether any balcony drainage is changing. The lower roof should be considered in the work plan before demolition begins.
02
Review completion together
If the balcony's water discharge or attachment details change, have the relevant designer and roofer review their effect on the roof below. Arrange an appropriate check of affected slate areas after the work. Keep dated photographs without assuming that every visible mark is a new defect. The aim is a documented handoff between the balcony project and the retained roofing.