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The bar has been raised
You will not earn this prerequisite using standard fixtures that only comply with the federal EPAct 1992. This prerequisite, first introduced in LEED 2009, raises the bar significantly. All projects must now reduce water use by at least 20% as a prerequisite, whereas earlier versions of LEED awarded a point for a 20% reduction. The baseline against which water savings are measured has also become more demanding. The LEED 2009 baseline for commercial lavatory faucets is 0.5 gallons per minute (gpm), whereas the previous baseline was 2.5 gpm. Note that this prerequisite addresses interior water use only, but can be coupled with other water credits addressing outdoor water use.
Plan on focusing on efficiency with ultra-low-flow or waterless fixtures, as well as overall conservation with strategies like rainwater capture and graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. reuse (these strategies are documented as an alternative compliance path in LEED Online). Careful attention to fixture selection and flow rates can help projects achieve 20% or greater interior water savings at minimal cost and without compromising comfort.
Follow these key steps
- Determine Full Time Equivalent (FTEFull-time equivalent (FTE) represents a regular building occupant who spends 8 hours a day (40 hours a week) in the project building. Part-time or overtime occupants have FTE values based on their hours per day divided by 8 (or hours per week divided by 40). Transient Occupants can be reported as either daily totals or as part of the FTE. Residential occupancy should be estimated based on the number and size of units. Core and Shell projects should refer to the default occupancy table in the Reference Guide appendix. All occupant assumptions must be consistent across all credits in all categories.) occupancy and Fixture Usage Groups.
- Determine the Baseline Case Water Use Budget for Indoor Water Use.
- Choose fixtures and water reduction or reuse strategies.
- Estimate the project’s water usage by creating a Design Case Water Use Budget.
- Use the LEED Online credit form to compare the baseline and design case water budgets to determine the water reduction percentage for the project.
- Complete the LEED Online credit form and upload water fixture cut sheets.
In the example illustrated in this bar chart, 21% savings is achieved by looking for savings in the fixtures that use the most volume of water: toilets, urinals, and showers. This example assumes 1.28 gpf toilets, 0.5 gpf urinals, and 2.0 gpm showers. Sinks are a less likely target because baseline use is already very low in many cases.
Only some water uses are under the LEED scope
Project teams often assume that if a water fixture or process on their project uses water, then it must fall under the scope of this credit. However, only specific "regulated" fixtures fall under the scope. The following uses, among others, are not within the credit scope. Following efficient practices is a great idea for these uses, but it's simply not covered under the scope here.
- "Process" water
- Pot- or bucket-filling sinks
- Bidets
- Laboratory sinks
- Dishwashers and other appliances
Key guidance from USGBC
Since LEED 2009 was launched, USGBC has developed and updated a key guidance document for WEp1 calculations: Water Use Reduction Additional Guidance. It provides indispensable guidance for fixture groups, total daily uses calculation, dual flush toilet flow rates, public metering faucet flow rate conversion, non-potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. use alternative compliance path and gender ratio guidance.
For example, this document provides key guidance on when a non-default male-female gender ratio is appropriate—essentially, modifications to the 50:50 ratio must be shown to apply for the life of the building, with specific exceptions allowed.
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A question of scope
As of an addenda issued in May 2011, USGBC has clarified the scope of this prerequisite for addition projects. For additions to existing buildings, only the fixtures within the project scope must be counted for WEp1. To earn points under WEc3, all fixtures necessary to meet the needs of occupants using the addition must be included, including those located within the preexisting building.
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FAQs for Water Use Reduction
Will the reviewers accept a spreadsheet as a plumbing fixture schedule in lieu of the plans from the Construction Documents?
A copy of the plumbing fixture schedule from the project's construction documents, outlining detailed information for each flush and flow fixture specified (including fixture manufacturer, model number and flow rate) helps the review team verify that those fixtures are part of the construction contract. In the absence of such documentation, a copy of project-specific specifications and details or a project-specific contractor’s submittal with manufacturer’s cut sheets highlighting flush and flow rates for each fixture specified can be provided.
In LEED review comments I've been referred to the Water Use Reduction Additional Guidance document. I didn't know this was a required reference document.
USGBC originally created this guidance document to address common questions project teams encountered when documenting WE credits. The calculations in these forms are fairly complex and are generally not addressed in the reference guide. The guidance document is intended to guide the user through the process of filling out the form, but is not intended to create any new requirements.
Should I include bar sinks? What about mop sinks or janitor sinks? Swimming pools? Safety showers? Bidets? Tub spouts?
If the bar sinks installed have a similar usage pattern and are similar fixture type as for those in kitchens then these should be included.
Mop sinks, janitor sinks, swimming pools, bidets, and safety showers are considered process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. and are not included. Consider only the showerhead and not the tub spout.
Additionally, commercial kitchen sinks and bar sinks including pot sinks, prep sinks, wash down, and cleaning sinks are considered process water and are not included.
However, pre-rise spay valves must be considered. If your project is registered after the 11/1/2011 addenda release then the pre-rinse spray valve flow rate must be 1.6 gpm or less in order to comply with the prerequisite. If your project has a pre-rinse spray valve that has a higher flow rate than 1.6 gpm, then the project is not in compliance and the pre-rinse spray valve would need to be revised in order to be eligible for LEED certification.
We provided showers to comply with the alternative transportation credit. Should they be considered in WEp1 calculations?
Yes. Once you enter the project occupancy the WEp1 form calculates the default daily FTE shower uses.
If those fixtures are outside the LEED Project Boundary, they should only be included if your project is LEED-CI, however.
Can you explain the 12-second duration for metering faucets?
This duration is intended to prevent LEED projects from claiming credit for reducing the duration below 12 seconds; durations less than 12 seconds are not permitted for LEED calculations as shorter intervals are insufficient for typical hand washing
Can I use a nonpotable water source to contribute to WEp1 compliance?
Yes. Although the focus is water efficiency of the installed fixtures, onsite sources of nonpotable water such as captured rainwater, graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area., air conditioner condensate, cooling tower bleed off water, etc., can be applied via an alternative compliance path. Refer to the Water Use Reduction Additional Guidance document for further information.
Our project does not have any eligible water fixtures in the project boundary. Can we comply with WEp1?
Yes, per LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. #10214: "A project without eligible water fixtures in the LEED-NC project boundary is exempt from WEp1. Should such a project wish to pursue points under WE Credit 3, they may do so by evaluating WEc3 performance based upon all of the fixtures that are necessary to meet the needs of the project occupants, even if they are located outside the project boundary."
We are having trouble finding EPAct-compliant fixtures. Is that a problem?
Not for individual fixtures. You only have to meet the LEED requirements for your fixtures as a group.
Where can I find a clear meaning of "public" and "private" as relevant to lavatory faucets?
Private usePrivate use applies to plumbing fixtures in residences, apartments, and dormitories, to private (non-public) bathrooms in transient lodging facilities (hotels and motels), and to private bathrooms in hospitals and nursing facilities. applies to plumbing fixtures in residences, apartments, and dormitories, to private (non-public) bathrooms in transient lodgingLodging are facilities that provide overnight accommodations to customers or guests, including hotels, motels, inns and resorts. facilities (hotels and motels), and to private bathrooms in hospitals and nursing facilities. Any fixtures that are not in one of those more residential-focused situations are considered to be public fixtures.
Our project is a factory with historically a 95% male workforce. The restroom design accounts for this. Can I argue that the male/female gender ratio is different than 50/50?
LEEDuser has seen numerous comments on our forums suggesting that reviewers are providing little leeway for situations like this, even in a case just like you describe. Even a 10% bump toward women to account for possible future trends was not deemed sufficient. At this point (February 2013), LEEDuser is not aware of clear guidance on when a nonstandard gender ratio would be accepted, nor are there any applicable LEED Interpretations for LEED 2009 projects. If you have any relevant experience on this, please let us know!
Are shower duration controls an acceptable water-saving strategy?
LEED assumes a baseline of 300 seconds for a shower, and LEEDuser has heard of review comments rejecting controls that would shorten this duration for the design case. A CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide or LEED Interpretation would likely be needed to make a case.
Can I include process water savings in order to earn an Exemplary Performance point?
Yes—refer to LEED Interpretation #5819, issued 8/31/2004 and modified 4/1/13 to apply to NC-v2.2 and NC-v2009 projects. Quoting the relevant text from LI #5819: “A whole building approach to process water must be used (including washing machines, dish washers, drinking fountains, cooling towers, etc.) The project must demonstrate a process water savings that is equal to or greater than 10% of the regulated water usage as calculated in WEc3. The project should obtain information on the average amount of water use for each type of equipment to determine an appropriate baseline and demonstrate that the increased efficiency compared to the baseline exceeds the 10% WEc3 threshold. Required submittals for this innovation would include: 1) A narrative explaining what strategies were used and how the baseline was developed. 2) Calculations demonstrating performance compared to the baseline. 3) Cut sheets showing water usage of equipment used.”
NC projects have also had success using Schools WEc4 as an ID credit. Also see LEED Interpretations #808 (issued 7/8/2004) and #5752 (issued 5/13/2005) for some history on this issue. You can also earn an EP point for 45% savings under the Water Use Reduction credit, but it appears, based on the most recent ruling, that the 45% savings should be based on regulated (non-process) fixtures alone.
Legend
- Best Practices
- Gotcha
- Action Steps
- Cost Tip
USGBC
Excerpted from LEED 2009 for Schools New Construction and Major Renovations
WE Prerequisite 1: Water use reduction
Required
Intent
To increase water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems.
Requirements
Employ strategies that in aggregate use 20% less water than the water use baseline calculated for the building (not including irrigation).
Calculate the baseline according to the commercial and/or residential baselines outlined below1. 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.
Commercial 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 lpfCommercial Urinals 1.0 (gpf) 4 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 faucets8.5 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 faucetsShowerheads 2.5 (gpm) at 80 (psi) per shower stall **** 9.5 lpm at 5 bar (58 psi) For projects with commercial pre-rinse spray valves, the flow rate must comply with the asME a112.18.1 standard of 1.6 gpm or less.
Residential fixtures, fittings, and appliances Current baseline (imperial units) Current baseline (metric units) Residential toilets 1.6 (gpf)*** 6 liters per flush (lpf)
Except blow-out fixtures: 13 lpfResidential lavatory (bathroom) faucets 2.2 (gpm) at 60 psi 4 lpm
8.5 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 faucetsResidential kitchen faucet Residential showerheads 2.5 (gpm) at 80 (psi) per shower stall**** flow rate ≤ 6.1 lpm
(no pressure specified; no performance requirement)* EPAct1992 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.
*** EPAct 1992 standard for toilets applies to both commercial and residential models.
**** residential shower compartment (stall) in dwelling units: the total allowable flow rate from all flowing showerheads at any given time, including rain systems, waterfalls, bodysprays, bodyspas and jets, must be limited to the allowable showerhead flow rate as specified above (2.5 gpm) per shower compartment, where the floor area of the shower compartment is less than 2,500 square inches (1.5 square meters). for each increment of 2,500 square inches (1.5 square meters) of floor area thereafter or part thereof, an additional showerhead with total allowable flow rate from all flowing devices equal to or less than the allowable flow rate as specified above must be allowed. Exception: showers that emit recirculated nonpotable waterNonpotable water: does not meet EPA's drinking water quality standards and is not approved for human consumption by the state or local authorities having jurisdiction. Water that is unsafe or unpalatable to drink because it contains pollutants, contaminants, minerals, or infective agents. originating from within the shower compartment while operating are allowed to exceed the maximum as long as the total potable water flow does not exceed the flow rate as specified above.
The following fixtures, fittings and appliances are outside the scope of the water use reduction calculation:
- Commercial Steam Cookers
- Commercial Dishwashers
- Automatic Commercial Ice Makers
- Commercial (family-sized) Clothes Washers
- Residential Clothes Washers
- Standard and Compact Residential Dishwashers
Potential Technologies & Strategies
WaterSense-certified fixtures and fixture fittings should be used where
available. Use high-efficiency fixtures (e.g., water closets and
urinals) and dry fixtures, such as toilets attached to composting
systems, to reduce water demand. Consider using alternative
on-site sources of water (e.g., rainwater, stormwater, and air
conditioner condensate) and graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. for nonpotable applications such
as custodial uses and toilet and urinal flushing. The quality of any
alternative source of water used must be taken into consideration based
on its application or use.
Technical Guides
Energy Policy Act of 1992 and amendments
Pages 62-69 of this legislation set federal standards for plumbing fixtures.
Energy Policy Act of 2005
The Energy Policy Act (EPA) addresses energy production in the United States. One example, the Act provides loan guarantees for entities that develop or use innovative technologies that avoid the by-production of greenhouse gases.
LEED 2009 Water Use Reduction: Additional Guidance
This document from USGBC offers guidelines to help you properly set up fixture usage groups in the LEED Online credit form, avoiding common mistakes associated with the water-efficiency prerequisite and credit.
Web Tools
WATERGY version 3.0
WATERGY is a spreadsheet model that uses water/energy relationship assumptions to analyze the potential of water savings and associated energy savings.
EPA Water Information links
This website offers links to state and regional water information.
Water Studies
This site provides a number of studies related to water.
Organizations
Alliance For Water Efficiency
AWE advocates for water-efficient products and programs and provides information related to water conservation.
EPA Office of Water
The Office of Water coordinates EPA's efforts to protect drinking water, oceans, watersheds and other aquatic ecosystems.
American Rainwater Catchment Systems Association
This organization promotes rainwater catchment in the U.S.
Oasis Grey Water Policy Center
Oasis Design, a maker of graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. systems, maintains this compilation of graywater laws and other resources on the regulation of graywater use.
LEED Online Form
This sample LEED Online form from a LEED for Schools Gold certified project provides an example of how to document WEp1 in a school with multiple flush and flow fixture usage groups. LEEDuser thanks Viridian for providing this sample.
Product Cut Sheets
Carefully research products and examine cut sheets to find fixtures and fittings meeting the credit requirements, as shown in these examples.
Samples
LEED Online Forms: Schools-2009 WE
The following links take you to the public, informational versions of the dynamic LEED Online forms for each Schools-2009 WE credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.
Version 4 forms (newest):
Version 3 forms:
- WEp1: Water Use Reduction
- WEc1: Water Efficient Landscaping
- WEc2: Innovative Wastewater Tech.
- WEc3: Water Use Reduction
- WEc4: Process Water Reduction
These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictions on these forms; for more information, visit LEED Online and click "Sample Forms Download."
Design Submittal
Documentation for this credit can be part of a Design Phase submittal.
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC.
31 Comments
10 second flow rate
I received the final comment for one of my LEED for Schools projects:
"Metered faucet duration has not been revised from 10-second duration to the default 12-second duration as required. The WEp1 Additional Guidance document states that design case autocontrol/metered faucet durations less than 12 seconds are not permitted for LEED calculations as they are insufficient for typical handwashing."
My project has in fact installed a metered faucet that has a flow rate of 10 seconds and not 12. We have documented this with a cut sheet that we uploaded on LEED Online. I realize that the default value is 12 seconds but this just seems silly of a reviewer to say. Who is to say that 10 seconds is insufficient? It's seems like an odd system if we cannot be incentivized for installing a lower flow rate.
LEEDuser team, any advice? This credit was denied based partially on this comment. Thanks for your help.
Hi Lauren,
Even with manufacturer supporting documentation, project teams are not allowed to submit a duration less than 12 seconds per the USGBC Water Use Additional Guidance document. Sorry.
It is mentioned that well and
It is mentioned that well and pond water does not count for this credit.
extracting water from onsite Aquifer using borehole can considered for this credit as the project will not be using any potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. source?
Thanks
Ameet, this would not be allowed. What you have described is very similar to using a potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. well.
school example in documentation toolkit?
I was wondering if the LEEDuser team could provide an example of a completed template for a school project in the documentation toolkit. While I appreciate the example provided, it is a fairly generic textbook office example. Schools have many different occupant types - teachers and staff, younger students, older students, parents and visitors, community after school users, etc. - whom all have differing fixture use requirements. Additionally, schools will often have multiple unisex restrooms which complicates matters as not all male occupants are using urinals. Personally, I find the guidance in how to address that particular component to be unclear.
Having a visual reference that is more relevant to a school environment would be of tremendous benefit.
Thanks.
William, there is now an example posted in the Doc Toolkit above. Thanks for Viridian for sharing this!
Thank you Tristan for the follow up, and Viridian for the example!
Trouble meeting prerequisite in school!
We are working with a school that is struggling to meet the prerequisite given programming and district requirements. The project currently plans to install 1.28 gpf toilets, 0.5 lavs, 1.3 gpm showers, and a 0.5 kitchen sink. 0.125 gpm urinals are only provided in the public restroom that will only be used by transient visitors. All staff restrooms are co-ed, therefore urinals are not provided. Urinals are also deemed not appropriate for elementary student use so not installed in student restrooms.
Our main barrier is that the students represent the main occupant water use category. Because the 1.28 gpf toilet represents exactly a 20% water use reduction but the 0.5 lavatories are baseline, the relatively minor water use of other fixtures and occupancy categories don't make up for the negative impact of the lavatories.
My question has to do with the lavatories used by students. The project could meet the prerequisite requirements with metered faucets provided for student hand washing. Unfortunately, metered faucets are not possible because the lavatories used for student hand washing are also used for other classroom functions where metering would be disruptive.
Has anyone run into a similar situation where the fixtures appropriate for the school programming do not meet the 20% minimum? Is there any argument for categorizing the student lavatories differently because they are used for other purposes?
Hi Cassidy,
Unfortunately, the student restroom lavatories cannot be categorized differently and a 0.5 gpm public lav must be utilized as the baseline. If automatic and/or metering faucets are not an option (because the same fixture is utilized in the classroom) you might consider an aerator to reduce the fixture flow rate (e.g. 0.35 gpm) on the restroom lavs.
As a side note for consideration – I’m not sure what version of the WEp1 Form you are utilizing (older forms default to a 15 second lavatory duration) but please note that the public lavatory duration should reflect a 30 second duration, as outlined in the LEED Reference Guide for Green Building Design and Construction, 2009 Edition (Updated June 2010) Addenda (WEp1 posted 2/2/2011).
Hope helpful!
Babies - Water Consumption
I'm working on a preschool project, which will have 30 babies between 4 months to 1 year-old; 30 babies between 1 to 2 years-old; 30 babies between 2 - 3 years-old; and 30 babies between 3 to 4 years-old. How should I develop the water calculation for these "students"? Should I include all babies as "students"?
I have not read specific guidance on this, however it would seem that any child (I'm not sure I'd label a 4 year old a baby) who can use the restroom and sink on their own or mostly on their own should be included.
Anyone have experience with this case?
I agree with Emily that any child that can use the restroom should be included. Potty-training practices differ in places, so I'll leave the rest up to your interpretation.
Availability of 2/4 LPF WCs
Dear all,
A Contractor of a LEED project has been struggling to find dual flush 2/4 LPF WCs in Lebanon (the Middle East).
Can someone please provide me with a list of suppliers who readily have 2/4 LPF WCs?
N.B: Although the project is in Lebanon, the Contractor is willing to import from abroad (preferably the Middle East region).
Many thanks..
George, you can get a lot of this information through the "GreenSpec Products" link in the right sidebar of this page.
Adjustable valve for WC fixtures
Dear all,
The project has 2/4 LPF WC fixtures specified, and the water calculations done accordingly.
The Contractor is suggesting a WC fixture with a maximum flush rate of 3/6 LPF, but with a regulating valve that can decrease the flush rate down to zero. In other words, the WC fixture can be adjusted to provide 2/4 LPF, but can be easily adjusted later on to a higher non-compliant flow rate.
Has anyone had experience with the USGBC with such types of WC fixtures?
Thanks..
George, I think USGBC would tend to assume that the fixture flow rate may be adjusted upwards in the future, and would have you assume the higher rate in your LEED documentation. I would encourage equipment that cannot have that adjustment.
School Kitchen Pre-Rinse and Wash Sinks
I am working on a high school project that includes a kitchen with both a pre-rinse sink and a three-tub sink that will have two faucets. I see that both pre-rinse sinks and kitchen sinks are among the fixtures that must be included in my water savings calculations, however the template defaults do not seem to accurately describe the number of daily uses nor the duration of the average use of these types of flow fixtures. Has anyone had any experience that might inform my decision about these figures? Thanks in advance.
Art,
I don't know if you could still use the information, but the new Version 4.0 of the form does not require a duration or daily uses number for the pre-spray valves. It is just a check that you have less than or equal to 1.6 gpm and you don't have to worry about the duration, number of uses, etc.
However, if you were using an older template like I was and had the following footnote to Table Flow Fixture Data, "a reasonable estimate MUST be provided for pre-rinse spray valves when selected in the table above," you would have wanted to enter a value. I found a Lawrence Berkeley National Lab study that seems reasonable for the pre-rinse spray valve: http://www.osti.gov/bridge/servlets/purl/962727-n3Dp1W/962727.pdf. This suggests schools use the valve 2.2 - 4 hours per day.
On the kitchen sink, I was just using the default of one use per FTEFull-time equivalent (FTE) represents a regular building occupant who spends 8 hours a day (40 hours a week) in the project building. Part-time or overtime occupants have FTE values based on their hours per day divided by 8 (or hours per week divided by 40). Transient Occupants can be reported as either daily totals or as part of the FTE. Residential occupancy should be estimated based on the number and size of units. Core and Shell projects should refer to the default occupancy table in the Reference Guide appendix. All occupant assumptions must be consistent across all credits in all categories. and 15 sec duration.
I really hope they will get these forms settled - just in time for 2012. :-/
Sonrisa - you are correct, the v4 form has been updated to reflect the LEED Reference Guide for Green Building Design and Construction, 2009 Edition (Updated June 2010) 11/1/2011 Addenda, which clarifies that for projects with commercial pre‐rinse spray valves, there is no longer a baseline performance standard from which to claim savings; rather, the prerequisite requires only that the flow rate comply with the ASME A112.18.1 standard of 1.6 gpm or less.
Private vs. Public Lavatory Faucets
I am working on two elementary schools, and the lower grade levels have private restrooms intended for individual student use in each classroom. The baseline for private lavatory faucets is 2.2 gpm, so installing 0.5 gpm faucets in these areas will help us to achieve a greater water savings, as long as these faucets are actually considered private. Page. 174 of the LEED for Schools 2009 reference guide states, "restrooms in commercial establishments where the fixtures are intended for the use of a family or an indivducal are considered private or private-use facilities." However, it also says, "If the classification for public or private usePrivate use applies to plumbing fixtures in residences, apartments, and dormitories, to private (non-public) bathrooms in transient lodging facilities (hotels and motels), and to private bathrooms in hospitals and nursing facilities. is unclear, default to public-use flow rates in performing the calcualtions associated with this credit.
Has anyone else encountered a similar situation and if so, how did you handle it?
Since the lower grade bathrooms serve the same function as the upper grade bathrooms, and since they are not intended for the use of a family or an individual, I would guess that they should be characterized as public lavatories for the purposes of this prerequisite/credit.
Hi Alison,
Not sure if you still need this info but private lavatory use applies to: plumbing fixtures in residences, apartments, and dormitories; to private (non-public) bathrooms in transient lodgingLodging are facilities that provide overnight accommodations to customers or guests, including hotels, motels, inns and resorts. facilities (hotels and motels); and to private bathrooms within hospitals and nursing facilities. All other facilities are considered to be public or public usePublic or public use applies to all buildings, structures, or uses that are not defined as private or private use..
The lower grade level classroom sinks you describe are considered public fixtures.
Hope helpful!
Classroom Sinks
Do classroom sinks, and art room sinks fall under lavatory sinks or are they not included in the baseline caculation.
WEp1 is limited to savings generated by the following water using fixtures: water closets, urinals, showerheads, public lavatory/restroom faucets, private lavatory/restroom faucets, public metering lavatory/restroom faucets, kitchen and janitor sink faucets, and metering faucets. Classroom and art room sinks do not fall within the scope of WEp1.
I am working on a school project that has both a classroom and administration component. There is a small "First Aid" room (100 SF) that has a sink in it. There is no full-time school nurse; the room will used as needed and not on a regular basis. Do you think that this sink should be included in the water use calculations?
It sounds like a lavatory sink? It would have to be included, but chances are it will have a negligible impact on your credit compliance.
Karen: The LEED BD+C Addendum dated January 8, 2010 removes janitors sink faucets from plumbing fixture water use table 1.
Classroom sinks
I found the language below in the LEED addenda for the applicable Reference Guide for LEED-S 2009. This clarification suggests to me that we can include the classroom sinks in our calculation if they are primarily used for handwashing. I also looked back at the reviewer comments for a previous project and those comments indicate that if classroom sink usage patterns are the same as bathroom sink usage patterns, we can include them in the calc.
"The “Public lavatory faucets” and “Private lavatory faucets” categories encompass all sinks used primarily for hand-washing regardless of location."
Has anyone had a recent project where classroom sinks were specifically rejected from the documentation?
Seems to me that if the classroom sinks are basically being treated as lavatory sinks, they should be included.
Hi Kimberly,
Yes, project teams are permitted to include classroom sinks provided the flow fixtures installed have a similar usage pattern and are similar fixture type as for those in bathrooms.
Classroom sinks are generally stainless steel sinks with two-handle faucets, the same as a kitchen sink but installed in a classroom. Occasionally we see metering faucets, but these are rare in my area for school classrooms. These can be used for handwashing, for cleaning up after projects using glue, or for any number of purposes. The primary use of classroom sinks is handwashing after using glue or paint, etc. These are sinks by definition, not lavatories, and even if they are used primarily for handwashing, that does not change the fact that they are sinks.
The faucets you normally find on classroom sinks are 2.5 gpm flow control faucets. If we count these somehow as lavatories, what is the baseline for these sinks? I do not believe it should be 0.5 gpm since they are not lavatories. Also, how do you quantify the use of classroom sinks vs. bathroom lavatories in order to put some use factor (uses per day) on them. I have seen many instances where classroom sinks are never used, they are full of books or covered up. Other classrooms use the sinks extensively such as art rooms and biology classrooms.
The additional guidance document indicates students washing their hands three times a day at lavatories. I assume this to be lavatories in the restrooms, not classroom sinks. So, how do we quantify the use of classroom sinks?
The fact is that we are replacing the traditional 2.5 gpm faucets with 0.5 gpm faucets in the schools we design. We should be able to get some credit somewhere for this major reduction in water use.
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