Geberit Pluvia simplifies building planning and permits optimum space utilisation. A diminished need for discharge stacks reduces outlay for underground drain connections and surface lines as well as the costs for the property developer. A Geberit Pluvia installation is less expensive than a conventional roof drainage system. Unlike conventional roof drainage methods, the Geberit Pluvia system functions as a siphonic system. The siphonic action ensures the drainage pipe system can fill up completely, thanks to the design of Geberit Pluvia roof outlets and the correct pipeline dimensioning, thus generating a negative pressure in the pipeline. The negative pressure in the pipe rapidly draws the rainwater by suction from the roof area, instead of merely allowing it to drain away. This also ensures an improved self-cleaning function. The benefits of Pluvia are a small pipe diameter, llarge self cleaning effect, maximum flow capacity, reduced requirement for downpipes, horizontal and groundworks, self-cleaning action, routing without slope, minimum number of fastening points.