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| v3 - LEED 2009

Water use reduction

WEc1 | Possible 11 points

Intent

To further increase water efficiency within tenant spaces to reduce the burden on municipal water supply and wastewater systems.

Requirements

Employ strategies that in aggregate use less water than the water use baseline calculated for the tenant spaces (not including irrigation). The minimum water savings percentage for each point threshold is as follows:

Building Use Reduction Process Use Reduction Points
30% AND 30% 6
35% AND 35% 8
40% AND 40% 11

Building water use

Calculate the baseline according to the commercial baselines outlined below. Calculations are based on estimated occupant usage. Include only the following fixtures and fixture fittings (as applicable): water closets, urinals, lavatory faucets, showers, kitchen sink faucets, and pre-rinse spray valves. [Europe ACP: Water Use Baseline]

Fixtures, Fittings, and Appliances Current Baseline (Imperial Units) Current Baseline (Metric Units)
Commercial Toilets 1.6 gallons per flush (gpf)*
Except blow-out fixtures: 3.5 (gpf)
6 liters per flush (lpf)
Except blow-out fixtures: 13.5 lpf
Commercial Urinals 1.0 (gpf) 4.0 lpf
Commercial Lavatory (restroom) Faucets 2.2 gallons per minute (gpm) at 60 pounds per square inch (psi),private applications only (hotel or motel guest rooms, hospital patient rooms)
0.5 (gpm) at 60 (psi)**all others except private applications
0.25 gallons per cycle for metering faucets
8.5 liters per minute (lpm) at 4 bar (58 psi), private applications only (hotel or motel guest rooms, hospital patient rooms)
2.0 lpm at 4 bar (58 psi), all others except private applications
1 liter per cycle for metering faucets
Shower 2.5 (gpm) at 80 (psi) per shower stall 9.5 lpm  at 5.5 bar (80 psi) per shower stall
Kitchen Faucet 2.2 (gpm) at 60 (psi) 8.5 lpm at 4 bar (58 psi)
Commercial Pre-rinse Spray Valves
(for food service applications)
Flow rate ≤ 1.6 (gpm)
(no pressure specified; no performance requirement)
Flow rate ≤ 6 lpm (no pressure specified; no performance requirement)
*    EPAct 1992 standard for toilets applies to both commercial and residential models.
**  In addition to EPAct requirements, the American Society of Mechanical Engineers standard for public lavatory faucets is 0.5 gpm at 60 psi (2.0 lpm at 4 bar (58 psi)) (ASME A112.18.1–2005).
This maximum has been incorporated into the national Uniform Plumbing Code and the International Plumbing Code.

AND

Commercial process water use

Employ strategies that in aggregate use less water than the water use baseline calculated for commercial equipment performance requirements as listed in the following table. Base the calculations on estimated occupant usage. Include only the following fixtures (as applicable): clothes washers, dishwashers, ice machines, food steamers, and combination ovens.

Exemptions from calculations:

  • Appliances and equipment that use water for human consumption may be excluded. Examples: bread misters, produce misters, soda machines, coffee-making machines, and fixtures used to fill sinks for washing produce.
  • Equipment, appliances, fixtures, and fittings that are not covered by the Energy Policy Act of 1992 (EPAct 1992), do not contribute toward the retail process, and are not commercially rated may be excluded. Example: a residential dishwasher in an employee break room.
  • Fixtures whose flow rates are regulated by health codes may be excluded. Example: fixtures used for filling dishwashing sinks in which water must be maintained at a certain temperature.

Commercial Equipment Baseline (Imperial Units) Baseline (Metric Units)
Commercial clothes washer, less than 80 lbs (36.3 kg) 9 gallons/cf/cycle 1,200 liters/m3/cycle
Commercial dishwasher
    Under counter, high temperature 1.98 gallons/rack 7.50  liters/rack
    Under counter, low temperature 1.95 gallons/rack 7.38 liters/rack
    Door type, high temperature 1.44 gallons/rack 5.45 liters/rack
    Door type, low temperature 1.85 gallons/rack 7.00 liters/rack
    Single tank rack conveyor, high temperature 1.13 gallons/rack 4.28 liters/rack
    Single tank rack conveyor, low temperature 1.23 gallons/rack 4.66 liters/rack
    Multi- tank rack conveyor, high temperature 1.1 gallons/rack 4.16 liters/rack
    Multi- tank rack conveyor, low temperature 0.99 gallon/rack 3.75 liters/rack
    Flight type 180 gph 681.37 lph
Commercial ice machines
    Ice machine, IMH (ice-making head) H < 450 lbs/day (<204.11 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, IMH (ice-making head)  H > 450 lbs/day (>204.11 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, RCU (no remote compressor) H < 1,000 lbs/day (<453.59 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, RCU (no remote compressor)  H > 1,000 lbs/day (>453.59 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, RCU (remote compressor)  H < 934 lbs/day (<423.66 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, RCU (remote compressor)  H > 934 lbs/day (>423.66 kg/day) < 25 gal/100 lbs ice < 95 liters/46 kg ice
    Ice machine, SCU (self-contained unit) < 35 gal/100 lbs ice < 133liters/46 kg ice
    Ice machine, water-cooled Must be on chilled loop Must be on chilled loop
    Ice machine, once-through water-cooled Banned Banned
Food steamer
    Steam cooker, batch cooking 8 gph/pan 3085.11 lph/pan
    Steam cooker, high production or cook to order 8 gph/pan 317.97 lph/pan
Combination oven  
    Countertop or stand mounted 40 gph 151.42 lph
    Roll-in 60 gph 227.12 lph
Other equipment Based on industry standards Based on industry standards
Notes: gph = gallons per hour; cf = cubic feet; lph = liters per hour; H = ice production.

For equipment not listed in the above tables, the project team may propose performance baseline requirements, with documentation supporting the proposed benchmark.

Alternative Compliance Paths (ACPs)

Europe ACP: Water Use Baseline

Projects in Europe may use the values defined by European Standards.

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