Basic Documentation

include automatic pumping, water treatment and
performance monitoring. While Green buildings are
inherently unique, pre-engineered rain water
catchment systems are beginning to emerge, saving
designers from reinventing the entire package.
Figure 6 illustrates a typical design. Rain water i
s
collected from the roof gutters and flows down to a
cistern for storage. In addition to straining and
filtering, treatment may include ultraviolet irradiation
or chemical disinfection. Even for non-potable
applications, it’s important to prevent biological
growth in the tank.
Rainwater Collecting Tank
BAS
Rainwater
Control
Panel
Greywater
Storage Tank
Water Treatment
Subsystem
From Gutters
and Drains
L
L
Greywater
Supply
L
Symbols
Level Sensor
Flow Sensor
Pump
Figure 6. Rain Water Collection Processes are Coordinated by the Building Automation System.
Pumps deliver the greywater for such uses as
restroom fixtures, landscape irrigation and cooling
towers. The BAS monitors water meters, pressure
sensors and level sensors to correctly operate the
pumps and treatment system, and to inform the
building operators. It’s important to integrate these
functions so the rain water system doesn’t become
separate in the minds of the operating staff.
Page 12 of 14 Siemens Industry, Inc.
Document No. 149-488
Metering
In the long run, water efficiency depends on effective
management and that requires information. In the
proposed standard for Green buildings, ASHRAE
requires meters on the facility’s water sources and
submeters for various identified uses (for example,
cooling towers, landscaping, specific tenants, etc.).
The data can support maintenance and
troubleshooting tasks. In some cases, measured
output from a rain water system affects billing
arrangements with the water and sewer utilities. It
also sets a baseline for evaluating improvements in
this facility or a new one. The Labs21 scorecard
awards point WE 4.1 for documenting such a
baseline.
Indoor Environmental
Quality
Safety is the primary issue in laboratory HVAC
design. From the perspective of a lab designer,
mainstream Green design documents understate the
point. The Labs21 EPC adds the prerequisite (EQ
P3) that the facility complies with the Laboratory
Ventilation standard from the American Industrial
Hygiene Association.
17
In particular, the Labs21
team points out the need for continuous control and
monitoring of fume hood operation and of space
17. American Industrial Hygiene Association, Laboratory
Ventilation Standard, ANSI NO. Z9.5. 1992. (Fairfax, VA).