8
/ ALBISTONE
®
G1 BENEFIT/G1 PLUS Skimmer Pools
3.
1. Installation of earth strip and drainage set – 1st Stage.
An earth strip in accordance with the applicable standards must be installed at the bottom of the excavation.
For more details on electrical wiring, see the Electrical Wiring section.
The foundation slab must be permanently drained.
For proper drainage of the foundation slab, it is necessary
to install drainage piping under the foundation; the piping should be connected to a drainage set (for drainage
pump shaft + drainage pump permanently connected to a power supply, see the following paragraph).
Ask your construction company for the ideal design of draining the pool foundation slab and any shafts,
according to the local geological conditions. Be sure, though, to account not only for groundwater but also
for rainwater, which may have equally negative effects on the pool shell as a whole, such as groundwater.
`
Drainage pump shaft –
a pipe
with a diameter of approx. 300 mm placed
vertically next to the foundation slab. Pour gravel
with an 8-to-16-mm grain size onto the bottom
of this pipe. There must be a height difference of at
least 500 mm between the gravel and the final
level of the pool foundation slab. The drainage
pump shaft serves as a sump for collecting
groundwater and rainwater. It must be provided
with a submersible pump. This pump must
trigger automatically when the water level in the
shaft rises and must be permanently connected
to the power supply via an underground cable.
The supply cable must run from the house
switchboard, and yet it must not be connected
through the switchboard in the technology
shaft. The pumped water must flow out of the
pool area and must not return under the pool
(see note on page 6 regarding the sewage and
rainwater system).
2. Backfilling with Gravel and Drainage Piping Installation, 2nd Stage.
Spread gravel with an 8–16mm grain size to form a layer about 100 mm thick the bottom of the
excavation. The 80-mm drainage piping is to be laid in the gravel layer, sloped down towards the
water outlet point (drainage pump shaft). The drainage pipe must be laid with a minimum slope of 1%.
In the layout, the mutual distances between the drainage pipes must not be greater than 800 mm.
All drainage pipes must be covered with a special geotextile before being overlaid with gravel and
concrete
Shaft
Earth wire
diameter of
8 mm
Earth strip FeZn
30x4
For pools over 8 metres long – add
a “middle” guide for the earth strip
FeZn 30x4.
The measured earth resistance must
comply with the applicable standards
and regulations.
Levelling the Bottom of the Excavation
and Drainage of the Foundation Slab
