ESD design guide for Australian Government buildings: Edition 2

case studies
Waalitj Building: Murdoch University
WATER
The Waalitj building utilises storm
water and black water to minimise
use of potable water. Rain water
from the roof of the building is used
to water the native garden and the
remainder flows into an ephemeral,
infiltration basin next to the car park,
encouraging biodiversity through
wetland bio-mimicry. The waste water
from the kitchen and toilets is treated
by an aerobic treatment unit (ATU)
before irrigating the courtyard lawn
and gardens through drip irrigation.
This provides a pleasant outdoor area
for staff and visitors.
A south facing colling pond,
landscaped and fed by storm water
(topped up by bore water) in front of
a low gable window takes advantage
of prevailing summer winds to deliver
cool air to the building for summer
heat relief.
Elsewhere on site there are rainwater
tabks, waterless toilets, greywater
diverters, a reverse osmosis
desalination unit, a flow form, drip
irrigation and several ponds serving
various purposes.
The average water use from the two
toilets and kitchen is 252L/day or
92kL/year.
IEQ
Operable walls form part of the
wall along the western edge of the
courtyard. These walls reflect and
channel winds into areas to aid cross
ventilation of the buildings. In the
winter, the walls are kept closed to
protect the buildings from cold wind.
Small north facing windows are used
to prevent excessive heat in summer
and prevent glare on computer
equipment. The architects decided
on large south facing windows to
naturally light the space.
Evaporative cooling ponds were
designed into the office space. These
ponds cool the hot easterly breeze
that enters the building in the summer.
The pond sources its water from the
excess rainwater from the roof.
Many of the walls are left untreated,
however, where plasterboard is used,
it is painted with organic finishes.
Planting has been used extensively
buildings to provide shade for the
buildings and for landscaping around
the complex. A mixture of low-water
use plants as well as fruit trees and
herbal gardens have been used.
MATERIALS
A great amount of thought and effort
went into the choice of materials.
Where possible, materials that were
recycled, or which incorporated waste
products, or have low embodied
energy were used. The industrial byproducts
used were sourced locally.
Concrete for the floor slab is made
of crushed concrete waste, windowglass
waste and coal fly ash. This
reduces the cost of cement as well as
reduces the amount of raw materials
used. It also diverts materials from
going to landfill.
The thermal mass walls are made of
10% cement with stabilised building
rubble made up mostly of recycled
red brick. They are also are made of
stabilised, rammed recycled earth.
The courtyard pavers are cement
mixed with 10-15% coal fly ash. This
reduced the embodied energy and
cost of the pavers.
The operable walls form part of the
wall along the western edge of the
courtyard. These are made from
recycled plastic panels.
EMISSIONS / TRANSPORT
The site is located within the Murdoch
University Campus, approximately 15
minutes walk from the main areas off
the campus. The centre has provided
approximately 100 bikes for free
use as a means of commuting from
the main campus to the technology
centre.
There are also public transport
facilities approximately 150m from the
site. The university also encourages
car pooling amongst staff.
REFERENCES
Murdoch University Environmental
Technology Centre
wwwies.murdoch.edu.au/etc/pages/waalitj/
wpages/backg.htm
ESD DESIGN GUIDE FOR AUSTRALIAN GOVERNMENT BUILDINGS 047