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Substructure
Compressed sand
Tank
Surround
(round gravel
max. grain 8/16 acc.
to DIN 4226-1)
Soil
Covering layer
Drinking water
telescopic lid
4.1
Construction site
Under all circumstances, the following points must be clarified prior to installation:
•
The structural suitability of the ground according to DIN 18196
•
Maximum groundwater levels which occur and drainage capability of the subsoil
•
Types of load which occur, e.g. traffic loads
An expert ground report should be requested from the local planning authority to determine the physical
characteristics of the subsoil.
4.2
Trench
To ensure that sufficient space is available for working, the base area of the trench must exceed the
dimensions of the tank by 500 mm on each side; the distance from solid constructions must be at least
1000 mm.
The embankment must be designed according to DIN 4124. The construction site must be horizontal and
plane and must guarantee sufficient load-bearing capacity.
The depth of the trench must be dimensioned so that the max. earth coverage (see point 2 – installation
conditions) above the tank is not exceeded. To use the system throughout the entire year, it is necessary
to install the tank and those parts of the system which conduct water in the frost-free area. The frost-free
depth is usually approx. 600 mm – 800 mm; precise information in this regard can be obtained from the
responsible authority.
A layer of compacted, round-grain gravel (grain size 8/16, thickness approx. 150 - 200 mm) is applied as
the foundation.
4.
Installation and assembly
