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Geberit Drainage Systems
Buried drain systems
7.1
Buried drain
systems overview
7
Buried drain systems
Underground drainage
The Geberit HDPE drainage system has a proven track
record for soil and waste installations. It can also be used
for under the building and up to 1 metre outside the
building envelope.
It is suitable for underground applications such as ground
pipes and domestic drainage pipes.
For underground systems, use pipe to a minimum of
PN4 rating. Do not use Geberit Silent-db20 as a buried
drain system.
Criteria for underground drainage pipes
1 Joint integrity
Environmental protection regulations do not permit
leaking drainage pipes. Geberit HDPE is a reliable water
drainage system which assures maximum dependability
with regard to joint integrity.
Special consideration for buried drain application
Geberit HDPE system is suitable for buried drain
application under the envelope of the building at
reasonable shallow depths and normal conditions.
When any of the following conditions exist please
contact Geberit for confirmation on its suitability.
• Pipes at depths greater than 4 metres
below ground level
• Pipes subjected to external water pressures
exceeding 2 metres head (high water table)
• Contaminated ground conditions
• Pipes subjected to internal negative pressures
• If during the construction stage high point
will be experienced due to heavy plant etc.
• If other manufacturers components are to be
incorporated into the system (puddle flanges
and other sleeving gaskets etc are used)
• Non domestic type discharges are expected,
for example:
- High volume discharges that could subject
the pipe to more than 1.5 bar pressure
- Combined high temperature and high
volume discharges
- Chemical waste
- Radioactive waste
2 Material
As in soil and waste drainage systems, the quality
of the material is the main criterion for underground
applications. In addition to the attack from the inside,
the pipes are also subjected to attacks from the outside.
Geberit HDPE provides resistance to the greatly
diversified types of chemical attack by the disposal
water, as well as by external factors (e.g. acidic soils).
Geberit HDPE can be successfully used to prevent
penetration underground and provide drainage in brown
field or contaminated sites. See the chemical resistance
list in section 8.3 for more information or contact
Geberit Technical.
3 Flexibility
Geberit HDPE is a flexible, operationally reliable drainage
system, even in soils in which a certain degree of settling
of ground is anticipated.