PROJECT
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receive potable water from the municipal water supply
and then supply the facilities via a booster pump set.
The borehole water, once implemented, will be treated to
supply the domestic water tank. There will be allowance
for controls for municipal and borehole water supply.
The soil and wastewater from the facilities will drain into
the sewer treatment plant and be treated and stored into a
recycled water storage tank of capacity 21.8m 3 . The water will
then be supplied to the facility’s toilet cisterns and urinals for
flushing via a booster pump set. A top-up water connection
from borehole water supply has been allowed for.
A sectional steel storage tank of capacity 174m 3 for
the fire water, which has its own pump sets as per fire
regulations, is also installed.
Reticulation
To ensure safe water use inside the buildings, dual
reticulation lines for recycled water and potable water
were installed using Mepla pipes. The reason for choosing
the Mepla solution was due to its low theft value, quick
installation, suitability for the lightweight steel structure
due to non-conductivity between the metals, and its
performance reliability for both hot and cold-water use.
The technical drawings of the building.
Hot-water generation and circulation
The hot-water generation allowed for two heat pump and
storage systems. Each system comprises a 250ℓ Kwikot
storage vessel inclusive of a 3kW backup element, with
hot water primarily generated from a 5.5kW Kwikot
heat pump. The hot-water reticulation forms a ring main
with hot-water supply and return through the Magna
3 Grundfos circulation pump. The smart circulation
pump was chosen because of its building management
system (BMS) compatibility, its intelligence of profiling
the user requirements/peak flows, and its low energy
consumption/efficiency.
Roof rainwater
Due to the architectural aesthetics of the building,
the Pluvia system is used to drain the bulk of the roof
rainwater to the rear end of the buildings. The water is
then collected into plastic JoJo tanks for reuse by the
retailer for gardening and other purposes.
Water-efficiency fittings
Where it was deemed practical, the water taps specified
and installed in the public ablutions are all water-saving
fittings from Grohe. The toilet cisterns throughout and
the urinals in the male ablutions are Geberit concealed
cisterns. The flush flow rates are set to minimise excess
water wastage. This is in keeping with the Green Star
requirements that the project aimed to achieve.
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The pump sets installed at the storage tanks.
May 2019 Volume 25 I Number 3