4.1
Connecting the inlet and venting pipes
To connect the inlet and venting piping there are prepared positions for the openings to be cut out of
the plastic ribbing. The pipes must extend at least 20 cm into the module. Should an installation over a
wider area be proposed, then there must also be an appropriately greater number of inlet pipes to
ensure an even distribution of the water.
4.2
Installation of the drainage blocks
The geo-textile must be laid out in the excavation that has an even bottom surface with an overlap of
not less than 30-50 cm. The modules are then positioned on the geo-textile (only laying down, never in
the standing position) and all fastened together with the fastening pieces. For fastening lengthwise as
well as widthwise, at least two fastening pins are required in each direction. When the system is to be
built in several levels, then the individual layers must be arranged both lengthwise and crosswise
(widthwise) to one another to ensure a stable interconnection. Before filling, the module must be
completely wrapped in the Geo-textile and special attention must be paid to ensure that all the ends
and edges of each fleece roll overlap by at least 30-50 cm. To conclude the installation, the excavation
is evenly backfilled and compacted. The terrain of the ground surface and substructure should be the
expected load to be prepared. If it is intended that grass should be sown over the GRAF drainage
blocks, then a heavy duty plastic sheeting should first be laid over the drainage blocks and this then
covered by an approximately 10 cm thick layer of clay otherwise the grass will dry out too quickly.
Otto Graf GmbH
Carl-Zeiss-Straße 2-6
D - 79331 Teningen
Tel: 0049/(0)7641/589-0
Fax: 0049/(0)7641/589-50
www.graf.info
info@graf.online.de
Stand: 12/2010
Graf Distribution SARL
45, Route d´Ernolsheim
F - 67120 Dachstein-Gare
Tel: 0033/388497310
Fax: 0033/388493280
www.graf.info
info@graf.fr
Version : 12/2010
Graf IBERICA Tecnología del Plástico S.L.
Sant Miquel 37 (Ver Situación)
ES – 17003 Girona
Tel: 0034/972913767
Fax: 0034/972913766
www.graf.info
info@grafiberica.com
Versión: 12/2010
4. Installation
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