Section 2: Individual LEED Credit Reviews
LEED Credit WE-3.1:
Additional strategies that might be considered
Water Use Reduction
Dual flush toilets (1.6/0.8 gpf)
Ultra low flush toilets (1.1 1.4/gpf)
Foot pedal controls for lavatories
Low flow urinals (rated at 0.5 gal/flush)
Maximize water efficiency within buildings to
Strategies that were deemed unlikely for typical
reduce the burden on municipal water supply
GSA buildings for cost or practicality purposes
and wastewater systems.
Stormwater collection and treatment systems
Greywater collection and treatment systems
Employ strategies that in aggregate use 20% less
Blackwater collection and treatment systems
water than the water use baseline calculated for
the building (not including irrigation) after
meeting Energy Policy Act of 1992 fixture
Basis for Cost Assumption
In the Courthouse and Office Building models,
water use reductions of 20 percent or more were
demonstrated through the following approaches:
Cost Impact = 1
1. Specifying 0.5 gpm faucets at bathroom lavatories.
This measure is enough to achieve the credit in
all the Courthouse and Office Building
scenarios, with or without employee showers.
2. Specifying 1.0 gpm faucets at bathroom lavatories and
1.5 gpm faucets at pantry sinks. In projects that
include employee showers, 2.0 gpm
showerheads are also included. This approach
works for the Office Building but does not
This LEED credit addresses internal plumbing
work for the Courthouse scenarios (where
fixtures, specifically faucets, showers, toilets, and
significant use of public restrooms is assumed).
urinals. Additional building water use sources, such
as cooling towers and dishwashers, are considered
Project assumptions are included in the
"process loads" and are specifically not included.
"Supporting Calculations" section below.
Because of this defined scope, the strategies that
would likely be employed to meet the credit criteria
could also be used to meet the 20 percent
include the following:
reduction goal, the aforementioned approaches
demonstrate that the credit can typically be
Low-flow lavatory faucets/aerators (rated at
achieved with common, inexpensive fixture types.
2.0 gpm or less)
As GSA's P100 criteria state that water
Ultra-low flow lavatory faucets (rated at 0.5
conservation shall be a requirement of all plumbing
systems, and that water saving plumbing fixtures
Electronic (infrared) sensors to automatically
shall be used, this credit was classified as a GSA
turn faucets on and off
standard, with no cost impact.
Low-flow kitchen sinks (rated at 2.0 gpm or
Low-flow showerheads (rated at 2.0 gpm or
GSA LEED COST STUDY