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LEED v4.1
New Construction
Water Efficiency
Indoor Water Use Reduction

LEED CREDIT

NC-v4.1 WEp2: Indoor water use reduction Required

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Requirements

Building Water Use
For the fixtures and fittings listed in Table 1, as applicable to the project scope, reduce aggregate water consumption by 20% from the baseline. Base calculations on the volumes and flow rates shown in Table 1. All newly installed toilets, urinals, private lavatory faucets, and showerheads that are eligible for labeling must be WaterSense labeled (or a local equivalent for projects outside the U.S.).
Table 1. Baseline water consumption of fixtures and fittings
Commercial Fixtures, Fittings, and Appliances Current Baseline (IP Units) Current Baseline (SI units)
Water closets (toilets)* 1.6 gallons per flush (gpf) 6 liters per flush (lpf)
Urinal* 1.0 (gpf) 3.8 lpf
Public lavatory (restroom) faucet 0.5 gpm at 60 psi all others except private applications 1.9 lpm at 415 kPa, all others except private applications
Private lavatory faucet* 2.2 gpm at 60 psi 8.3 lpm at 415 kPa
Kitchen faucet (excluding faucets used exclusively for filling operations) 2.2 gpm at 60 psi 8.3 lpm at 415 kPa
Showerhead* 2.5 gpm at 80 psi per shower stall 9.5 lpm at 550 kPa per shower stall
* WaterSense label available for this product type gpf = gallons per flush gpm = gallons per minute psi = pounds per square inch lpf = liters per flush lpm = liters per minute kPa = kilopascals
Projects located where standard supply pressure is different than the LEED baseline supply pressure may calculate the water consumption of flow fixtures and fittings at the local standard supply pressure.
Appliance and Process Water Use
Install appliances, equipment, and processes within the project scope that meet the requirements listed in the tables below. Existing appliances intended for reuse in the project are not required to meet the requirements in Table 2.
Table 2. Standards for appliances
Appliance Requirement
Residential clothes washers ENERGY STAR or performance equivalent
Commercial clothes washers ENERGY STAR or performance equivalent
Residential dishwashers (standard and compact) ENERGY STAR or performance equivalent
Prerinse spray valves ≤ 1.3 gpm (4.9 lpm)
Ice machine ENERGY STAR or performance equivalent and use either air-cooled or closed-loop cooling, such as chilled or condenser water system
gpm = gallons per minute
lpm = liters per minute *Projects in Europe may install residential appliances meeting the EU A label.
Table 3. Standards for processes
Process Requirement
Heat rejection and cooling No once-through cooling with potable water for any equipment or appliances that reject heat
Cooling towers and evaporative condensers Equip with:
  • makeup water meters
  • conductivity controllers and overflow alarms
  • efficient drift eliminators that reduce drift to maximum of 0.002% of recirculated water volume for counterflow towers and 0.005% of recirculated water flow for cross-flow towers
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Addenda

4/21/2023 – Updated: 5/9/2023
Reference Guide Correction
Description of change:
Add the following as a second bullet under International Tips:

"o Where local building code conflicts with LEED prescriptive requirements, project teams may select fixtures that comply with local code and compensate by selecting more water-efficient fixtures for other fixture types, provided that the flow rate for the fixture is the lowest allowable by code, and the project meets in aggregate the required 20% reduction from LEED baseline. Provide an excerpt of the local code highlighting the flow rate requirements when submitting for review."
Campus Applicable
No
Internationally Applicable:
No
4/9/2021 – Updated: 4/20/2021
Rating System Correction
Description of change:
Revise the intents for both WE prerequisite Indoor Water Use Reduction and WE credit Indoor Water Use Reduction to read as follows:
"To reduce indoor potable water consumption and preserve no and low cost potable water resources."
Campus Applicable
No
Internationally Applicable:
No
4/9/2021 – Updated: 4/19/2021
Reference Guide Correction
Description of change:
Below the Further Explanation section titled "Occupant Types" add a new section titled "Campus or Municipal Alternative Water Sources" that reads as follows:

"Campus or Municipal Alternative Water Sources
Projects may count future infrastructure for reclaimed water systems in Water Efficiency credit calculations if:
 the future systems will be functional within 2 years of project occupancy,
 the project provides documentation, such as a signed contract, confirming that the reclaimed water will be provided to the project within a 2-year period from project occupancy, and
 the project provides confirmation that the reclaimed water supplier has agreed to supply the volume of treated wastewater or seawater claimed by the project."
Campus Applicable
No
Internationally Applicable:
No
11/9/2020 – Updated: 11/30/2020
Rating System Correction
Description of change:
In the sentence below Table 1. Baseline water consumption of fixtures and fittings, delete the following phrase: "the supply pressure must be consistent in the baseline and proposed case."

Revise the sentence below Table 2. Standards for appliances so that it reads as follows: "*Projects in Europe may install residential appliances meeting the EU A label."
Campus Applicable
No
Internationally Applicable:
No
11/10/2020 – Updated: 11/25/2020
Reference Guide Correction
Description of change:
In the International Tips section, delete "+++" in the bullet point that begins "The EU ..." so that the sentence reads as follows:

"The EU A label for residential appliances is an acceptable alternative to ENERGY STAR. The EU Ecodesign and Labelling framework establishes minimum performance standards for the energy and environmental performance of appliances and products."
Campus Applicable
No
Internationally Applicable:
No
7/25/2019 – Updated: 7/30/2019
Reference Guide Correction
Description of change:
After the Referenced Standards section in the Further Explanation section, add new section:

"Exemplary Performance
Achieve 55% savings."
Campus Applicable
No
Internationally Applicable:
No
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LEEDuser expert

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emily reese moody

LEED AP BD+C, LFA, EcoDistricts AP, ENV SP, Fitwel Ambassador, WEDG Professional, ActiveScore AP, GGP, GPCP, GCP

Jacobs
Sustainability Director, Certifications & Compliance

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© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Building Water Use
For the fixtures and fittings listed in Table 1, as applicable to the project scope, reduce aggregate water consumption by 20% from the baseline. Base calculations on the volumes and flow rates shown in Table 1. All newly installed toilets, urinals, private lavatory faucets, and showerheads that are eligible for labeling must be WaterSense labeled (or a local equivalent for projects outside the U.S.).
Table 1. Baseline water consumption of fixtures and fittings
Commercial Fixtures, Fittings, and Appliances Current Baseline (IP Units) Current Baseline (SI units)
Water closets (toilets)* 1.6 gallons per flush (gpf) 6 liters per flush (lpf)
Urinal* 1.0 (gpf) 3.8 lpf
Public lavatory (restroom) faucet 0.5 gpm at 60 psi all others except private applications 1.9 lpm at 415 kPa, all others except private applications
Private lavatory faucet* 2.2 gpm at 60 psi 8.3 lpm at 415 kPa
Kitchen faucet (excluding faucets used exclusively for filling operations) 2.2 gpm at 60 psi 8.3 lpm at 415 kPa
Showerhead* 2.5 gpm at 80 psi per shower stall 9.5 lpm at 550 kPa per shower stall
* WaterSense label available for this product type gpf = gallons per flush gpm = gallons per minute psi = pounds per square inch lpf = liters per flush lpm = liters per minute kPa = kilopascals
Projects located where standard supply pressure is different than the LEED baseline supply pressure may calculate the water consumption of flow fixtures and fittings at the local standard supply pressure.
Appliance and Process Water Use
Install appliances, equipment, and processes within the project scope that meet the requirements listed in the tables below. Existing appliances intended for reuse in the project are not required to meet the requirements in Table 2.
Table 2. Standards for appliances
Appliance Requirement
Residential clothes washers ENERGY STAR or performance equivalent
Commercial clothes washers ENERGY STAR or performance equivalent
Residential dishwashers (standard and compact) ENERGY STAR or performance equivalent
Prerinse spray valves ≤ 1.3 gpm (4.9 lpm)
Ice machine ENERGY STAR or performance equivalent and use either air-cooled or closed-loop cooling, such as chilled or condenser water system
gpm = gallons per minute
lpm = liters per minute *Projects in Europe may install residential appliances meeting the EU A label.
Table 3. Standards for processes
Process Requirement
Heat rejection and cooling No once-through cooling with potable water for any equipment or appliances that reject heat
Cooling towers and evaporative condensers Equip with:
  • makeup water meters
  • conductivity controllers and overflow alarms
  • efficient drift eliminators that reduce drift to maximum of 0.002% of recirculated water volume for counterflow towers and 0.005% of recirculated water flow for cross-flow towers

LEEDuser expert

headshot

emily reese moody

LEED AP BD+C, LFA, EcoDistricts AP, ENV SP, Fitwel Ambassador, WEDG Professional, ActiveScore AP, GGP, GPCP, GCP

Jacobs
Sustainability Director, Certifications & Compliance

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