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Wavin AS+
Technical Manual
Installation
In the case of mixed systems, rainwater and sewage must
leave the building via separate downpipes, collecting pipes
or underground and collector pipes. Underground and col-
lector pipes or collecting pipes must, for hydraulic reasons, be
jointed together as near as possible to the connecting sewer
outside the surrounding land. This jointing should be located
in a shaft with open flow.
In exceptional cases (e.g. if the surrounding area is built-up),
the waste water and rainwater pipes may only be jointed on
the property if this occurs in the direct vicinity of the outer wall
of the building.
Application of DN 90
DIN EN 12056 specifies that DN 90 is suitable not only for
collecting connection pipes, but also for downpipes and
underground and collector pipes. This means that a complete
waste water system – from the tap points right down to the
first cleaning access or transfer shaft – can be configured
using a minimum number of components, allowing the client
to save both materials and money.
The DN 90 also offers other advantages compared to the
diameter of the DN 100. A nominal diameter of 90 is ideal for
connecting water-saving toilets, because the smaller diameter
accelerates outflow. For this reason, DIN 1986-100 specifies
DN 90 for use with 4 and 4.5-litre water-saving cisterns.
This nominal diameter requires little space when used with
today’s commonly employed narrow installation shafts
A DN-90 collecting connection conduit can be used
as follows:
Up to a length of 10 m,
For connecting up to two 6-litre cisterns,
For connecting up to six items of sanitary equipment,
For a fall of 1 cm /m (1:100),
For up to three changes of direction (90° or 2 × 45°).
DN 90 therefore allows buildings of up to ten storeys in height
to drain waste water in a functional and norm-compliant way
using standard sanitary equipment.
DN 90 can, subject to compliance with the corresponding
hydraulic discharge units (flow rate of 0.7-2.5 m/s), also be
sued to connect to a DN 90 underground and collector pipe
that runs up to the property boundary.
