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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To maximize water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems.
Requirements
Project teams earn points by achieving the following percent reductions for both building water use and process water use. The minimum water savings percentage for each point threshold is as follows:
Percentage Reduction |
Points |
---|---|
30% |
1 |
35% |
2 |
40% |
3 |
Building water use
Employ strategies that in aggregate use less water than the water use baseline calculated for the building (not including irrigation). The baseline shall meet the requirements of the Energy Policy Act (EPAct) of 1992 and subsequent rulings by the Department of Energy, requirements of the EPAct of 2005, and the plumbing code requirements as stated in the 2006 editions of the Uniform Plumbing Code or International Plumbing Code pertaining to fixture performance. Calculations are based on estimated occupant usage and must include only the following fixtures and fixture fittings (as applicable to the project scope): water closets, urinals, lavatory faucets, showers, kitchen sink faucets and pre-rinse spray valves. Fixtures used for clinical use, such as surgical scrub sinks and exam room sinks are exempt from this calculation. [Europe ACP: Water Use Baseline]Table 1: National efficiency baselines for commercial and residential water-using fixtures, fittings and appliances
Fixtures, Fittings, and Appliances |
Current Baseline (Imperial Units) |
Current Baseline (Metric Units) |
---|---|---|
Toilets |
1.6 gallons per flush (gpf)* |
6 liters per flush (lpf) |
Urinals |
1.0 (gpf) |
4.0 lpf |
Lavatory (restroom) faucets |
2.2 gallons per minute (gpm) at 60 pounds per square inch (psi), private applications only |
8.5 liters per minute (lpm) at 4 bar (58 psi), private applications only (e.g., hospital patient rooms) |
Pre-rinse spray valves |
Flow rate ≤ 1.6 (gpm) |
Flow rate ≤ 6 liters per minute (lpm) |
Showerheads |
2.5 gpm at 80 psi per shower stall**** |
9.5 lpm at 5.5 bar (80 psi) per shower stall |
* EPAct 1992 standard for toilets applies to both commercial and residential models. |
AND
Process water use
Employ strategies that in aggregate use less water than the process water use baseline calculated for equipment performance requirements as listed in Table 2. Calculations are based on estimated occupant usage and shall include only the following fixtures (as applicable to the project scope): clothes washers, dishwashers, ice machines, food steamers and combination ovens. Exemptions from calculations:- Appliances and equipment for which water is used toward human consumption may be excluded. For example, bread misters, soda machines, coffee making machines, misters for produce and fixtures used to fill sinks for washing produce.
- Fixtures whose flow rates are regulated by health codes may be excluded from the calculation. For example, regulated medical equipment is excluded. See WE Prerequisite 2 for requirements applicable to heat rejecting medical equipment.
Table 2: Equipment performance requirements table
Equipment |
Baseline (Imperial Units) |
Baseline (Metric Units) |
---|---|---|
Commercial Clothes Washer – less than 80 lbs (36.3 kg) |
9 gallon/CF/cycle |
1,200 liters/m3/cycle |
Commercial Dishwashers |
||
Undercounter – high temp |
1.98 gallon/rack |
7.50 liters/rack |
Undercounter – low temp |
1.95 gallon/rack |
7.38 liters/rack |
Door type – high temp |
1.44 gallon/rack |
5.45 liters/rack |
Door type – low temp |
1.85 gallon/rack |
7.00 liters/rack |
Single tank rack conveyor – high temp |
1.13 gallon/rack |
4.28 liters/rack |
Single tank rack conveyor – low temp |
1.23 gallon/rack |
4.66 liters/rack |
Multi-tank rack conveyor – high temp |
1.1 gallon/rack |
4.16 liters/rack |
Multi-tank rack conveyor – low temp |
0.99 gallon/rack |
3.75 liters/rack |
Flight type |
180 gallon/hour |
681 liters/hour |
Commercial Ice Machines |
||
Water-cooled ice machine capacity < 450 lb/day (<204.11 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine capacity > 450 lb/day (>204.11 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity < 1000 lb/day (<453.59 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity > 1000 lb/day (>453.59 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity < 934 lb/day (<423.66 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity > 934 lb/day (>423.66 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine Self Contained Unit (SCU) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Water-cooled ice machines |
Must be on closed cooling loop |
Must be on closed cooling loop |
Water-cooled ice machines once through cooling |
Not allowed |
Not allowed |
Food Steamers |
||
Boiler type steam cooker – batch cooking |
8 gallon/hour/pan |
30.28 liters/hour/pan |
Boilerless type steam cooker – high production/cook to order |
8 gallon/hour/pan |
30.28 liters/hour/pan |
Combination Oven |
40 gph |
151.42 lph |
Countertop or stand mounted |
40 gph |
151.42 lph |
Roll-in |
60 gph |
227.12 lph |
Other equipment |
Performance baseline based on industry standards |
Alternative Compliance Paths (ACPs)
Europe ACP: Water Use Baseline
Projects in Europe may use the values defined by European Standards. See all forum discussions about this credit »What does it cost?
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To maximize water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems.
Requirements
Project teams earn points by achieving the following percent reductions for both building water use and process water use. The minimum water savings percentage for each point threshold is as follows:
Percentage Reduction |
Points |
---|---|
30% |
1 |
35% |
2 |
40% |
3 |
Building water use
Employ strategies that in aggregate use less water than the water use baseline calculated for the building (not including irrigation). The baseline shall meet the requirements of the Energy Policy Act (EPAct) of 1992 and subsequent rulings by the Department of Energy, requirements of the EPAct of 2005, and the plumbing code requirements as stated in the 2006 editions of the Uniform Plumbing Code or International Plumbing Code pertaining to fixture performance. Calculations are based on estimated occupant usage and must include only the following fixtures and fixture fittings (as applicable to the project scope): water closets, urinals, lavatory faucets, showers, kitchen sink faucets and pre-rinse spray valves. Fixtures used for clinical use, such as surgical scrub sinks and exam room sinks are exempt from this calculation. [Europe ACP: Water Use Baseline]Table 1: National efficiency baselines for commercial and residential water-using fixtures, fittings and appliances
Fixtures, Fittings, and Appliances |
Current Baseline (Imperial Units) |
Current Baseline (Metric Units) |
---|---|---|
Toilets |
1.6 gallons per flush (gpf)* |
6 liters per flush (lpf) |
Urinals |
1.0 (gpf) |
4.0 lpf |
Lavatory (restroom) faucets |
2.2 gallons per minute (gpm) at 60 pounds per square inch (psi), private applications only |
8.5 liters per minute (lpm) at 4 bar (58 psi), private applications only (e.g., hospital patient rooms) |
Pre-rinse spray valves |
Flow rate ≤ 1.6 (gpm) |
Flow rate ≤ 6 liters per minute (lpm) |
Showerheads |
2.5 gpm at 80 psi per shower stall**** |
9.5 lpm at 5.5 bar (80 psi) per shower stall |
* EPAct 1992 standard for toilets applies to both commercial and residential models. |
AND
Process water use
Employ strategies that in aggregate use less water than the process water use baseline calculated for equipment performance requirements as listed in Table 2. Calculations are based on estimated occupant usage and shall include only the following fixtures (as applicable to the project scope): clothes washers, dishwashers, ice machines, food steamers and combination ovens. Exemptions from calculations:- Appliances and equipment for which water is used toward human consumption may be excluded. For example, bread misters, soda machines, coffee making machines, misters for produce and fixtures used to fill sinks for washing produce.
- Fixtures whose flow rates are regulated by health codes may be excluded from the calculation. For example, regulated medical equipment is excluded. See WE Prerequisite 2 for requirements applicable to heat rejecting medical equipment.
Table 2: Equipment performance requirements table
Equipment |
Baseline (Imperial Units) |
Baseline (Metric Units) |
---|---|---|
Commercial Clothes Washer – less than 80 lbs (36.3 kg) |
9 gallon/CF/cycle |
1,200 liters/m3/cycle |
Commercial Dishwashers |
||
Undercounter – high temp |
1.98 gallon/rack |
7.50 liters/rack |
Undercounter – low temp |
1.95 gallon/rack |
7.38 liters/rack |
Door type – high temp |
1.44 gallon/rack |
5.45 liters/rack |
Door type – low temp |
1.85 gallon/rack |
7.00 liters/rack |
Single tank rack conveyor – high temp |
1.13 gallon/rack |
4.28 liters/rack |
Single tank rack conveyor – low temp |
1.23 gallon/rack |
4.66 liters/rack |
Multi-tank rack conveyor – high temp |
1.1 gallon/rack |
4.16 liters/rack |
Multi-tank rack conveyor – low temp |
0.99 gallon/rack |
3.75 liters/rack |
Flight type |
180 gallon/hour |
681 liters/hour |
Commercial Ice Machines |
||
Water-cooled ice machine capacity < 450 lb/day (<204.11 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine capacity > 450 lb/day (>204.11 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity < 1000 lb/day (<453.59 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity > 1000 lb/day (>453.59 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity < 934 lb/day (<423.66 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity > 934 lb/day (>423.66 kg/day) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Air-cooled ice machine Self Contained Unit (SCU) |
<25 gal/100 lb ice |
<95 liters/46 kg ice |
Water-cooled ice machines |
Must be on closed cooling loop |
Must be on closed cooling loop |
Water-cooled ice machines once through cooling |
Not allowed |
Not allowed |
Food Steamers |
||
Boiler type steam cooker – batch cooking |
8 gallon/hour/pan |
30.28 liters/hour/pan |
Boilerless type steam cooker – high production/cook to order |
8 gallon/hour/pan |
30.28 liters/hour/pan |
Combination Oven |
40 gph |
151.42 lph |
Countertop or stand mounted |
40 gph |
151.42 lph |
Roll-in |
60 gph |
227.12 lph |
Other equipment |
Performance baseline based on industry standards |