In modern architecture, an attic is an upstand of the edge of the roof, which is particularly common in flat roofs. The parapet must be raised to such an extent that the minimum heights specified in the technical rule for waterproofing can be complied with for raising the waterproofing above the surface of the decking. These are:
For a roof with a circumferential parapet, at least one emergency overflow or drain must be provided in order to be able to rule out a backflow of surface water up to the height of the parapet, for which neither the roof structure (static) nor the waterproofing (pressure case pressing water) is usually designed.
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