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Credit language
© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Building water use
Employ strategies that in aggregate use 20% 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 (e.g., hospital patient rooms) |
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 20% 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: Minimize Potable Water Use for Medical Equipment Cooling 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 |
||
Air-cooled ice machine capacity > 450 lb/day (>204.11 kg/day) |
||
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity |
||
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity > 1000 lb/day (>453.59 kg/day) |
||
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity |
||
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity > 934 lb/day (>423.66 kg/day) |
||
Air-cooled ice machine Self Contained Unit (SCU) |
||
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 |
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?
Cost estimates for this credit
On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.
Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.
This information is also available in a full PDF download in The Cost of LEED v4 report.
Learn more about The Cost of LEED v4 »Frequently asked questions
See all forum discussions about this credit »Addenda
Add the following to eligible fixtures section:
"For healthcare projects, fixtures used for clinical use related to medical procedures, such as surgical scrub sinks and exam rooms sinks, in hospitals and medical office buildings are excluded from the water use calculations. Medication room sinks, utility room sinks, and other exam/procedure/observation room sinks for clinical use are also excluded. Should exam/procedure/observation room sinks be used primarily for hand-washing, they may be included in the water use calculations at the project team’s discretion under the public lavatory category. If included, project teams should provide a narrative explaining the usage assumptions for these sinks.
Lavatories in hospital inpatient bathrooms and inpatient rooms are considered private. The inpatient lavatory and water closet should use the default residential usage assumptions (of five times per day per residential occupant), unless specific project conditions warrant an alternative. Lavatories in hospital inpatient rooms (outside the bathrooms) are considered private if used by patients and/or staff similarly to a residential lavatory, or can be exempt if they are used by staff primarily for medical or clinical use.
Nutrition station (pantry) sinks and hospital staff lounge sinks should be included in the water use calculations under the kitchen sink category."
"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."
Please reference specific prerequisites and credit in the Credit Library for a complete table.
"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."
Can municipally supplied treated seawater for toilet flushing be used as a strategy for earning WEp1 and WEc1 Water Use Reduction?
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Update October 1, 2013
Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated.
10/1/13 notes: link resource and edit ruling: http://www.usgbc.org/resources/seawater-guidance
No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the prerequisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path.
However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy.
**Update October 1, 2013: Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated.
Original ruling July 1, 2012
No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the prerequisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path.
However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy."
Can municipally supplied treated seawater for toilet flushing be used as a strategy for earning WEp1 and WEc1 Water Use Reduction?
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Update October 1, 2013
Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated.
Original ruling July 1, 2012
No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the pre-requisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path.
However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy."
----------
10/1/13 notes: revise ruling and update resource: http://www.usgbc.org/resources/seawater-guidance
No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the prerequisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path.
However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy.
**Update October 1, 2013: Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Building water use
Employ strategies that in aggregate use 20% 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 (e.g., hospital patient rooms) |
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 20% 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: Minimize Potable Water Use for Medical Equipment Cooling 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 |
||
Air-cooled ice machine capacity > 450 lb/day (>204.11 kg/day) |
||
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity |
||
Air-cooled ice machine with remote condensing unit (w/o remote compressor) capacity > 1000 lb/day (>453.59 kg/day) |
||
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity |
||
Air-cooled ice machine with remote condensing unit (with remote compressor) capacity > 934 lb/day (>423.66 kg/day) |
||
Air-cooled ice machine Self Contained Unit (SCU) |
||
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 |
Performance baseline based on industry standards |