Siphonic drainage

Products Custom designed and foamed-in connecting sleeve Loose-type/face flange design Suitable for trapezoidal sheet metal roofs Connects to PE-pipes Connects to SML-pipes
SitaDSS Profi
SitaDSS Profi
SitaDSS Profi Flange
SitaDSS Profi Flange
SitaDSS Multi
SitaDSS Multi
SitaDSS PE-Pipes and Fittings
SitaDSS PE-Pipes and Fittings
SitaDSS Ravana
SitaDSS Ravana
SitaDSS Indra emergency drainage
SitaDSS Indra emergency drainage
SitaDSS Indra main drainage
SitaDSS Indra main drainage




The modern way of flat-roof drainage

Sita's DSS System utilizes the laws of physics (i.e. hydrostatic water pressure) for draining roofs.

Already at low quantities of rain, the down-pipes cross-section closes by itself, thereby creating the necessary negative pressure even if pipes are only partially filled. Sita drains outfitted with SitaAirstop prevent air from being admitted into the pipes that would otherwise occur through the forces of the “Coriolis effect”.

The rainwater flowing into the down-pipes creates a vacuum in the collecting pipe that efficiently drains the roof area and piping system using a “suction-lifting” effect.

The fact that the pipes are filled combined with the pressure created by the difference in height result in a high flow speed and thus in significant construction and economic benefits.

Benefits of siphonic drainage:

  • Optimum use of space through non-sloping installation directly underneath ceiling
  • Fewer down-pipes = less risk of damage through impact
  • Minimum of work required for underground piping
  • Fewer or no inspection shafts = less maintenance work
  • Self-cleaning pipe system through high flow velocity
  • Also ideal for emergency drainage