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BEAM P
LUS FOR
N
EW
B
UILDINGS
W
ATER
U
SE
(W
U
)
V
ERSION
1.2
W
U
P2 M
INIMUM
W
ATER
S
AVING
P
ERFORMANCE
Copyright © 2012 BEAM Society Limited. All rights reserved.
Page 125
5
W
ATER
U
SE
5.P
P
REREQUISITE
W
U
P2 M
INIMUM
W
ATER
S
AVING
P
ERFORMANCE
E
XCLUSIONS
None.
O
BJECTIVE
Reduce the consumption of fresh (potable) water through the application
of water saving devices that have proven performance and reliability.
R
EQUIREMENT
Demonstrate that the use of water efficient devices leads to an estimated
aggregate annual saving of 10%.
A
SSESSMENT
Given the paucity of available data for Hong Kong and variability of
circumstances for different buildings and uses, BEAM seeks to provide
flexibility in the assessment by:
allowing Clients to submit justification for the award of credits, or
using the pro-forma calculation method described below.
Calculation shall be provided to determine the reduction of water
consumption in the project space compared with a similarly occupied
space whose water fittings and appliances conform to a baseline
performance. Project teams may use the template as a point of reference
when performing their calculations.
The calculation takes into account the number of occupants, male to
female ratio, and the number of operational days per annum. This
information must be supplied by the Client and may be stated in the
design brief or Owner’s Project Requirements (OPR).
Water use is based either on a ‘per operation’ basis or as the product of
flow rate and operation time. The default assumptions for the calculation
procedure are given in Appendix 8.6.
Number of water devices installed and frequency of use must be the
same for both the baseline and project case. Clients must provide the
manufacturers’ specifications for the performance of installed water
devices.
The Client shall submit a report that:
details all installed devices and their water consumption rate or
discharge volume; and
details devices installed to reduce the potential wastage of water
due to unnecessary operation of taps, etc;
The submitted report shall contain the following information:
number of operational days per annum;
number of occupants; and
male to female ratio.
There should be two sets of tables, one for the project space, and one
for the base line space.
In the table, each type of water using device shall be listed and all data
used shall be referenced to the source. The calculation shall include
water taps for bath, basin, pantry, kitchen, and also shower heads, and
exclude water closets, urinals, water features, appliances and irrigation.
There should be separate entries for water use in male and female
facilities. Tabular data should be similar to the following format: