Architect and Builder Magazine South Africa September/October 2014 | Page 21

Within the EY Tower, the
criss-crossing bridges
above the atrium and
the use of natural light
create a comfortable
and visually appealing
working environment

Water Conservation
• Rainwater is harvested and captured in a
tank with a 72,000 litre capacity. A further
rainwater tank provides 84,000 litres. These
storage tanks are located in the basements.
• Separate pipes supply rainwater to toilets
and urinals for flushing, thereby decreasing
the need for potable water. Potable water
use is estimated at 0.48L/day/m2.
• Water-efficient sanitary fixtures have been
installed within the building. This reduces
the amount of potable water required
and further reduces the amount of water
drained down into the sewerage system
with an estimated 0.57L/day/m2.
• Fire Systems testing in buildings is typically
responsible for millions of litres of water
wasted due to weekly routine pump testing
and other tests to the systems. This water
is heavily oxidised and not suitable for
reuse and would normally be discharged
to the sewer. To preserve the potable
water, wastage isolation valves are fitted
on every floor to ensure individual draining
of each floor. This means that in cases of
malfunction, only the relevant floor can be
tested and drained without draining the
fire system for the entire building. 99% of
the water used in routine testing is recycled
back into storage tanks. These design
strategies allow for a saving of millions of
litres of water per annum.

The project design and construction
processes have identified opportunities to
reduce the production of construction and
demolition waste and identified suitable
recycling/reuse opportunities.
Easily accessible recycling waste storage
stations for cardboard, paper products, glass,
plastics and metal have been provided.
Passive design strategies, which were
extensively modelled by WSP in Africa’s Green
by Design team, have been incorporated
to reduce the amount of energy needed to
achieve a comfortable indoor temperature.
For example, Tower Block 2 (consisting of
concrete walls and brick cavities) is orientated

Resource Efficiency
A waste management plan was implemented
to reduce the amount of construction and
demolition waste going to landfill by 70%.
102 Rivonia Road

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