Real Estate Investor Magazine South Africa September 2013 | Page 48
GETTING STARTED
be supplemented by rainwater harvested from
the roofs. The rainwater harvesting alone will
reduce potable water demand by 56%.
The building contains 50% evaporative
cooling systems and 50% air-cooled chiller
systems. While evaporative cooling systems
are energy eff icient, they use a substantial
amount of water. This consumption will be
monitored.
Energy
An existing Egoli Gas main gas line runs past
the property. The building therefore makes
use of a gas powered tri-generation plant. Trigeneration is the simultaneous production of
electrical energy and heat and cooling from a
single energy source such as natural gas. Trigeneration is commonly referred to as CCHP
(combined cooling, heating, and power
generation).
Further energy savings will be achieved
through efficient lighting. The lighting power
density has been reduced to below 2.5W/m²
per 100 Lux. A digitally addressable lighting
system (DALI) has been installed for 99.26%
of the usable area. This allows individual
light fittings to be programmed according to
need, and facilitates automatic dimming and
switching of lighting based on occupancy and
daylight availability in the space. Lighting and
light power will be individually monitored per
f loor and energy uses greater than 100KVA
will be separately metered. No light beam on
the piazza or in the garden is directed into
the night sky, so external light pollution is
minimised.
Materials
Over 60% of the building’s steel has more
than 90% post-consumer recycled content,
massively reducing the embodied energy. Fifty
percent of all the timber has been sourced
from Forest Stewardship Council-certified
suppliers.
A minimum of 20% of the bulky materials
permanently installed in the building will
be procured from w ithin 40 0k m of the
construction site, reducing carbon emissions
t hat wou ld ot her w ise re su lt f rom t he
transportation of materials.
When you are developing buildings it’s very
important what type of materials you use.
There are a number of green materials which
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September 2013 SA Real Estate Investor
will add value to your building, one such is
clay bricks. Clay bricks provide sustainability
consequent to t hei r longe v it y, proven
durability and structural integrity beyond
100 years. This mitigates future carbon debt
associated with replacement and maintenance
of less durable walling materials. Clay bricks
contain natural mineral properties recognized
for meeting all necessary requirements for
healthy living, their inert qualities assure no
release of toxic fumes or VOC’s to impinge
on air quality and the mass enhanced R-value
they provide to SANS 204 compliant brick
walls assures superior thermal comfort and
the lowest heating and cooling energy usage
in