Sealing membrane for waterproofing of roofs, balconies, loggias and arcades with solvent-free liquid plastics in accordance with DIN18531 Part 2 with e.g. PMMA (polymethyl methacrylate resin), EP epoxy resin, PUR polyurethane resin; suitable for roof drains from the HL62, HL64 and HL65 series.