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.
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.
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.
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.
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.
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.
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.
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.
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.
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
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.
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."
Not for individual fixtures. You only have to meet the LEED requirements for your fixtures as a group.
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.
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!
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.
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.
Check local codes and incentives for water-saving opportunities and restrictions. Rebates are common, as are plumbing codes restricting some water-savings technologies such as waterless urinals, graywater reuse, on-site wastewater treatment and reuse, rainwater harvesting, composting toilets, and other strategies.
Graywater and rainwater collection systems may offer the potential for non-potable water to be used in interior applications, helping to achieve this prerequisite, and the additional water-reduction credit.
Perform a Water Balance Study for the entire project to make informed decisions about where to focus water savings efforts. Look for all water sources on the site, such as stormwater, graywater, and onsite water, and note opportunities for using that water for interior water use and or irrigation.
Calculating outdoor water use is not required for this prerequisite . However, understanding how indoor water use compares to outdoor water use can help you gauge where to focus reduction efforts for the greatest benefit. Some water saving strategies address both indoor and outdoor water needs holistically. For example, graywater from interior sink fixtures can be collected for landscape irrigation.
Graywater used for landscaping cannot be calculated for this prerequisite, but can be counted in WEc1: Water Efficient Landscaping.
Are composting toilets an option? While not common, composting toilets can go a long way toward achieving this prerequisite. They affect programming and layout, so consider them early.
Consider setting water-reduction goals higher than the 20% reduction required by this prerequisite. Many projects are able to achieve 30%–40% savings with little or no impact on cost. First-time costs for water savings above 20% can be minimal since project teams will already be integrating water-saving techniques for this prerequisite.
Estimate the project’s baseline water needs and determine the baseline water use budget for indoor water use. This helps determine where the most effective water-saving technologies can be applied.
Establish goals for water use reduction and include these goals in the Owner’s Project Requirements (OPR) for EAp1: Fundamental Commissioning. Consider aiming higher than a 20% reduction. Many of the same strategies used for this prerequisite will also apply to WEc2: Innovative Wastewater Technologies and WEc3: Water Use Reduction.
Determine the numbers and types of occupants in the building. The water use calculation is based on occupant use and the number of full-time equivalent (FTE) occupants, including employees and visitors, not the number of water fixtures installed.
The FTE occupancy number you use here must be consistent with the FTE occupancy numbers used in all other LEED credits, including:
Determine user groups for the various fixtures as not all occupants may be using all the fixtures; for example, employee restrooms and customer toilets in a retail store will have different use patterns.
The baseline for commercial lavatory faucets has been changed in LEED 2009 to 0.5 gpm. The previous baseline for commercial lavatory faucets was 2.5 gpm. Take note of this more stringent requirement compared with earlier versions of LEED.
This prerequisite only includes core water uses—bathroom lavatories, water closets, urinals, showers, kitchen faucets and pre-rinse sprays. Janitors’ sinks, pot fillers, and tub faucets can be left out as they are used to fill containers with a fixed water volume regardless of the flow rate. "Kitchen sinks" includes all sinks in public or private buildings that are used with patterns and purposes similar to a sink in a residential kitchen. Break room sinks would be included; commercial kitchen sinks are not included. Lavatory faucets refer to hand-washing sinks, regardless of location, but lab or healthcare sinks with regulated flow rates are excluded. Pot-filling sinks can be excluded.
Appliance and process water uses such as clothes washers, dishwashers, cooling tower make-up, and others, do not need to be included in the LEED water reduction calculations. However, teams do have the option of earning an additional point for reduced appliance and process water as part of an exemplary performance point, building on the 30%–40% water-use reduction for WEc3: Water Use Reduction.
Well water and pond water are not considered “reused” water for the purposes of this credit and must count as potable water—so you don’t get credit for substituting them for conventional water sources. Water types that do count as reused are: graywater (lavatory, sink and shower water), rainwater, treated wastewater, air-conditioner condensate, reverse-osmosis reject, and sump-pump water.
Part-time students are now included as a type of occupant in Schools. Part-time students are calculated in the same manner as part-time staff.
Select water-efficient fixtures and strategies. Gather information on applicable fixtures including manufacturer, model number, and flush or flow rates.
For residential projects, showers typically use more water than any other fixtures due to the duration of use. For commercial projects, toilets and urinals typically use more water. Water-saving strategies should target the most consumptive fixtures to achieve greatest water reductions.
Compare the baseline and design case water use budgets to determine the water reduction percentage goals for the project. The LEED Online credit form has a built-in calculator to facilitate this calculation. Repeat this process until final selection of water fixtures and strategies have been made and the project’s water reduction goals are satisfied.
Size graywater and rainwater systems to match non-potable water demand, for needs such as toilet flushing, cooling tower makeup, and irrigation.
Untreated rainwater, graywater, and blackwater may corrode plumbing systems, or lead to biological growth. Teams should plan for water treatment, filtration, or using corrosion-resistant materials. The use of seawater for toilet flushing, although very uncommon, can cause similar problems.
Plumbing piping must be doubled for interior water fixtures when graywater or rainwater is reused in addition to potable water. This is likely to add upfront costs, while potentially reducing water and sewer charges.
Sensors on toilets and faucets are perceived as saving water. However, several studies have shown that while they may offer some hygiene or other operational benefits, they increase water use substantially, due to “phantom flushes” and faucets running longer than needed. If you do choose lavatory sensors, look for models with adjustable flow durations. Although the LEED calculation estimates a standard 30-second use, setting the flow duration to a shorter time interval can help save water. In other words, adjusting the LEED design case calculation to a more accurate (and shorter) flow duration can help you meet the 20% reduction.
Aerators are very cost-effective, costing only a few dollars per fixture. Installing an aerator allows you to chose the sink fixtures that are desired and not have to worry if they are low–flow—simply purchase compatible aerators in addition to the fixtures. You can also easily retrofit existing faucets with low-flow aerators.
Many commercial toilets can be retrofitted with dual-flush flushometers, costing less than installing new dual-flush toilets. Check with manufacturers for retrofitting compatibility.
Integrate efficient water fixture specifications into construction and design development documentation.
Specify signage for water strategies that may require special instructions for use. This may include occupant signage for operating dual-flush toilets, indicating non-potable water, and operational signage for distinguishing pipes carrying reused water.
If reusing graywater or rainwater, ensure that key system components such as treatment and cisterns are not removed during value engineering.
Fill out the LEED Online credit form and upload water fixture cut sheets to LEED Online.
You must use an Alternative Compliance Path to document savings from a non-potable source in LEED Online. Adjust the design case total water use volume to account for the annual amount of non‐potable water. Then use the adjusted design case total water use to recalculate the percent reduction of water use for all fixtures. Additional documentation or calculations may include but are not limited to plumbing drawings, calculations and system capacity to support quantities provided, and any analysis to confirm the availability of the non‐potable water source.
The contractor ensures that the correct fixtures have been purchased and any applicable water reuse systems or specified metering systems have been installed.
Make sure supply pipes carrying non-potable water are clearly labeled and color-coded to avoid inadvertent cross-connection with potable water lines.
Apply for water-reduction incentives and rebates through municipal water authorities.
Provide building managers with manuals for all irrigation systems and controls, fixtures and fittings, water-reuse technologies, on-site water treatment systems, and unconventional products.
Consider installing permanent water metering for ongoing monitoring of the project’s water use. A sub-metering system can help operations staff detect problems early and facilitate future LEED-EBOM certification.
Train cleaning and operations staff to maintain atypical fixtures such as waterless urinals, water sensors and other fixtures.
Excerpted from LEED 2009 for Schools New Construction and Major Renovations
To increase water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems.
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.
The following fixtures, fittings and appliances are outside the scope of the water use reduction calculation:
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.
Pages 62-69 of this legislation set federal standards for plumbing fixtures.
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.
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.
WATERGY is a spreadsheet model that uses water/energy relationship assumptions to analyze the potential of water savings and associated energy savings.
This website offers links to state and regional water information.
This site provides a number of studies related to water.
AWE advocates for water-efficient products and programs and provides information related to water conservation.
The Office of Water coordinates EPA's efforts to protect drinking water, oceans, watersheds and other aquatic ecosystems.
This organization promotes rainwater catchment in the U.S.
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.
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.
Carefully research products and examine cut sheets to find fixtures and fittings meeting the credit requirements, as shown in these examples.
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:
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."
Documentation for this credit can be part of a Design Phase submittal.
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.
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 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?
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.
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.
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!
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?
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).
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.
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).
George, you can get a lot of this information through the "GreenSpec Products" link in the right sidebar of this page.
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?
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.
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.
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.
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.
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.
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.
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.
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.
Tips and screenshots on LEED Online documentation.
Reducing water use by toilets and urinals can help earn points in both WEp1 and WEc3, as well as in WEc2.
As water is saved in lavatory faucets, kitchen sinks and showers, you’ll need less hot water, saving energy.
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