Sewage pipe - which nominal widths are binding?

Sewer pipes need to be properly sized so that sewage can drain properly and not cause blockages. For this reason, there are rules that the legislature has laid down in a DIN standard for the nominal widths of sewage pipes.

Which nominal widths are binding for lines?

  • Collecting lines min. DN 70
  • Basic lines Min. DN 100
  • Downpipes min. DN 80

The slope of the sewer pipe must not have any reductions and must be continuous.

Which nominal widths are binding for connections according to DIN?

Application nominal pipe size
Bidet, wash basin DN 40
Shower, sink DN 50
Sink, dishwasher DN 50
Washing machine up to 6 kg DN 50
Washing machine up to 12 kg DN 70
urinal DN 50
WC up to 6 liters DN 80
WC up to 9 liters DN 100
Floor drains DN 50/70/100
Tips & Tricks The regulations can be found in DIN 1986 Drainage Systems for Buildings and Land Part 100 as well as in connection with DIN EN 752 and 12056