Protection or drainage slab with hollow cams or recesses - has duct-shaped depressions in region of the slab main plane, extending between cam openings

摘要

In the region of the slab (11) main plan (13) are formed duct-shaped depressions (14), extending between the cam openings (12b). The depressions contain drainage apertures (15) for removing excessive water from the cam cavities to a level below the slab main plane. Pref. the cams are frusto-conical, or pyramidal, with the tips folded back to the slab main plane. The depressions may stretch between the cam apertures at an angle to each other. USE/ADVANTAGE - For vegetation covered flat roofs etc., with increased drainage capacity.