Office
UNIT
DESIGN STAGE
3.3.4 Reducing Water use
Case study of
Hong Kong
Green Building
Council
Figure 3.3.32 Water saving
fixtures in office pantry
(Source: Hong Kong Green Building
Council)
Using a water-saver
outlet to reduce excessive
discharge from the faucet
and achieve up to 84% in
water savings.
A dual flush sensor
promotes best practice in
water economy (short or
long flush) and hygiene in
toilets.
Reduction of water for
flushing-20,000m
3
/year.
To protect the environment, no
bottled water is used.
The selected dispenser has
OASIS® Quick Change Filtration
and is NSF certified under
Standards 42 and 53 with
carbon filtration, lead, cyst and
reduction media.
Figure 3.3.33 Dual flush sensor
(Source: Hong Kong Green Building Council)
Hand washing sensor reduces
potable water for pantry use
and hand washing-4,500m
3
/
year.
Figure 3.3.34 Hand
Washing Sensor
(Source: Hong Kong Green
Building Council)
DESIGN STAGE
3.3.5 Water Recycling
Benefits of Green Office Building
• Reduce water demand on water
main
• Reduce cost of water usage
• Reduction in the amount of
fresh water needed for sewage
conveyance
• Reduction in the total amount of
fresh water drawn from natural
water bodies
• Similarly a reduction in the volume
of sewage entering the public
sewage infrastructure
Green Strategies for Office Building
Water Recycling
Overview for Office Building
To enhance water economy, some of the water discharged by the building can
be recycled so that fresh water consumption can be reduced. Water recycling
schemes include, but are not limited to, recycling rain water, greywater,
condensate water, cooling tower bleed-off water and fire services water.
BEAM Plus NB V1.2 WU 4
Harvesting of rainwater shall lead to a reduction of 5% or more in the
consumption of fresh water.
Recycled greywater shall lead to a reduction of 5% or more in the consumption
of fresh water.
Office
BUILDING
z
Recycle rainwater for irrigation
or cleansing uses
z
Recycle air conditioning conden-
sate for flushing use
z
Recycle
from low
contaminated waste water in
office
z
Recycle waste water during fire
services system annual inspec-
tion for cleansing
z
Recycle cooling water bleed-off
for flushing use
Figure 3.3.35 Rainwater
recycling system
Green
Roof
Rainwater
Storage
Tank
Figure 3.3.36 Rainwater
collection system
Rainwater
collection
Rainwater
Storage
Tank
Filtration
System
Automatic
Irrigation
System
Rainwater Harvesting System makes
use of rainwater collected on green
roofs, exterior walls and at ground
level for non-potable and safe use
purposes. A rainwater harvesting
system has a significant effect on the
reduction of potable water used for
irrigation.
Case study of
Hysan Place:
Rainwater Collection System.
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