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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 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.
WEp1 LEED Online Form
This sample form for WEp1 is from a real project whose name was changed on the form. (Note that WEp1 was achieved for this project even though this sample displays that the form was not completed.)
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: NC-2009 WE
The following links take you to the public, informational versions of the dynamic LEED Online forms for each NC-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
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.
406 Comments
Rainwater use applicable for non-Retail/Healthcare projects?
The USGBC document, "Water Use Reduction Additional Guidance" states, "Retail and Healthcare projects may apply on-site 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. sources for fixtures and 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. use reduction."
Does this mean only Retail and Healthcare projects are able to count rainwater use towards water reduction calculations? Or can any project use this strategy for WEp1?
Timothy, any project can use 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. sources to meet requirements.
Thanks Tristan. I wish the Additional Guidance document would make that clear!
Just a reminder to Healthcare projects who may be reading this, you can not use 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. inside the building for plumbing fixtures. You'll be in a big heap of trouble with the AHJ and the Joint Commission.
You can use non potable water for landscaping and cooling tower blow down.
Vandal-resistant aerator
Hello,
We just got our review back for a new construction of an office building.
For this credit we had a comment from the reviewer, that we have never encounter before. They asked to provide documentation that shows the aerator selected for the locker room faucet is vandal-resistant as required.
What does that mean and what is the documentation we need to provide?
Thank you in advance.
A lot of times aerators get removed after installation, this is why vandal resistant types are available. That said, this sounds like a classic GBCI "phantom requirement" and very annoying! It's probably in an addenda or 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 / LI somewhere. I would try to research it and check the date of the decision. If it is after the registration date of your project, you can argue that it doesn't apply to it. Good luck!
Greywater recirculated
Our water reduction due to fixtures and fittings only is 38%. We have recirculating greywater in the project that will be recirculated to toilets. This will bring our reduction to 42%. I know this can be claimed for WEc2 - Innovative Technologies but can this also be claimed for WE prerequisite 1? How can we document it on the form?
Thanks!
Residential Dual Flush Calculations
When you are calculating, dual flush weighted averages for residential usage, the guidance says 1:2 ratio of full to low flush uses for both females and males. That works great with 3 uses, but residential is 5 uses. Does that mean 2 full and 3 low? Or are we using fractions?
Limit of water flow?
Hello everyone!
We are having problems with the WEp1 water use reduction.
First our calculations were wrong, and now, we´ve realized that we need to reduce a lot of the water flow in the metering faucets.
We can buy water reducing valves to install in those metering faucets, which will reduce the water flow to a GPC of 0,1. In this way, we can achieve a 60% water use reduction.
I´d like to know if there is a limit of lower GPC that the USGBC allow us to use.
Does anyone have already had any issues with that?
Thanks.
Hi Enrique,
You should be able to select Public Lavatory in fixture family and then Metering in fixture type. Once you do that the table changes that row to GPC instead of GPM. You need to upload your backup for that conversion. GPM rate x 12 sec / 60 = GPC. If you have a 0.5 gpm faucet, that means a 0.1 GPC.
That should be all you have to do. Revise the table, provide the GPC in the table per your conversion, upload your conversion calculation.
Water Use Reduction Additional Guidance document is very helpful.
Thank you very much Michelle.
I got it. Seems like it´s all right now. My only question is regarding a low GPC now. Do you know if there is a low limit of GPC for the metering faucets?
Thank you!
Hi Enrique,
As far as I know, only with respect to not going lower than 12 sec in the duration for the calculation. Less than that is not considered enough for hand washing. You could have lower GPM than 0.5 though I don't usually see it where I am.
Thank you Michelle, I have just one more question.
I´ll have to appeal for that prerequisite, but now sure how to do it.
I´ve already changed all the calculations and data. I´ve uploaded more documentation in the form, and clicked on the "Ready for Review" button.
But I can´t find where I could write to explain all the changes we made regarding their denial.
Is it necessary to write them, somewhere in the leedonline, with an explanation addressing the issues in the technical advice provided with the denial of the prerequisite?
Or shoul I just submit for review?
Thanks
Hi Enrique,
We generally write a narrative for each review comment response that is part of the revised documents that we upload for each credit. In this narrative, we duplicate the comment and guidance, then we explain how we have addressed each and every point. We find that this makes it easier for reviewers to see that we have caught everything. So yes I would definitely provide a narrative explaining the changes you've made in response to the comments and upload that also before you submit for review.
Also FYI if you are simply responding to initial review comments and have not received your "final" review, this is not an Appeal. An Appeal would mean that you would be paying an additional review fee to submit information a third time for that specific credit only. Otherwise you are still just responding to comments.
Thanks a Lot Michelle, I´ll try to go back and upload a narrative.
And regarding the review fase. It´s a final review. But it´s the first time they ask us about this prerequisite. I guess I´ll have to pay anyway.
Once again, thank you very much.
Hi Enrique,
My understanding is that it is inappropriate for a reviewer to "come up with" a comment in the final review that they did not flag in the initial review unless you have added a credit or changed your compliance path. If I were you, I would be asking about that.
Michelle, that´s a really important issue.
That´s exactely what happened. This comment never came up during the project review, and it´s not a new credit, its a prerequisite.
The proper way to ask about that would be through a Formal Inquirie? Or sending then a message by LEED online?
i´m afraid to loose the 25 days period to ask for an appeal.
Enrique,
I sympathize. This is a tough area. I think that I would use Feedback and identify your issue as being related to review comments then make your case that this issue was not flagged during the initial review. Particularly with a Prerequisite, that is just brutal. It doesn't sound like you have a compliance problem, just a documentation issue. That is vastly different.
Both Feedback and Contact Us through the USGBC website can take some time, especially if it's not a simple answer. But you don't have a lot of choices when it comes to direct contact.
I have to admit that I'm a bit worried about the new membership levels and how they are attached to customer service and technical support. Moving forward large firms that are able to pay higher annual fees will get their questions answered in a guaranteed 24 or 48 hour period. Small guys will have to wait. This can obviously be a big deal if you can't get the answer you need in a timely fashion. Timely support has been an issue for them for a while. I guess I hoped they would handle it by improving their response times for everyone, not just for a favored corporate few.
Good luck.
Dear Michelle,
I thank you very much, for all your attention with our issue. I´ll let you know how it ended.
Once again. Thank you!
I have some experience with the feedback route and even requesting a review extension. I've been successful with both.
A recent project review required clarifications that we anticipated taking longer than 25 days due to the location of the project site. We made the request for an extension with a brief statement as to why and it was granted fairly quickly. The response seemed genuinly supportive of helping the project be successful and not strictly punative in their assessment of our request.
I also received a very prompt and clear reply to a feedback question recently and am cautiously optomistic that the new, more approachable, GBCI model will be successful.
Good luck!
I'll chime in and just say that over the years many reviewers have "added" issues to comments in response to our clrificaitons, etc. There seems to be no way to fight this formally, but I agree that you should use the Feedback optio, or just email your Review Team directly and clearly state your rationale and concerns. We have had success calling things to their attention when they seem unfair - and without paying for the appeal process.
Hi there, thank you all for sharing those rich experiences related to our issue.
It really helped a lot.
We´ve decided to appel for this prerequisite, but we´ll write them, using the feedback option.
I´ll let you know when we get their answer about all this.
Thank you once again. It was really very helpful!
Hotel Spa Water Use - LEED NC
I am working on a high-end hotel that has a spa installed. Is the spa considered in the water use reduction calculations or is it considered process as water?
Thank-you
The spa would be considerd just like any other retail space in a hotel. Any of the standard bathroom facilities (toilets / showers / bathroom sinks) as well as a "kitchen sink" if the staff have access to a "coffee station" type sink would be included for those users (you'd want to include a separate user group for the people in the spa -- both staff and transients). Any other types of plumbing fixtures (steam room, individual sinks in massage rooms, etc.) would be 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..
Thank-you for the quick response! A couple more q's..
Is the shower-head baseline (2.5 gpm) to be used to evaluate the water use reduction in the individual spa-rooms?
If there is a staff hand sink in the individual spa-room then is this water-use to be included in the water-use-reduction calculation or is it 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.?
Public and private lavatory faucets encompass all sinks used primarily for hand-washing regardless of location (February 2, 2011 Addenda); so if the staff hand sink described above is used primarily for hand washing then it would need to be included.
Urinal pre-wash and fuzzy control
Hi all,
How would you set the water use for urinals that:
1. Have a 2 liter pre-wash that may be used or turned off
2. Have fuzzy control for the flush (2 to 4 liters)
The worst case is 6 liters, but the actual water usage depends on building operation and the fuzzy control. Do you think it is fair to exclude the pre-wash and pick up the middle value for the fuzzy controlled flush (3 liters)?
Thanks in advance,
Template rounding for Design Case-Urinal
We have completed our template with all fixtures included and are at 39.97% savings!!! UGH. As we dig into the template to see if there is a way to reach that 40% threshold, and thus 3 more points we have noted the 0.125 GPF (1 pint) urinal is rounding to 0.13 GPF. This small rounding make the difference between 39.97% savings and 40.03% savings. Has anyone run into something similar? We are planning submit our own spreadsheet of calculations, but was wondering if anyone had has success ina similar situation.
Hi Rebekah,
While the calcs are performed in the prerequisite for (WEp1) check the associated credit form (WEc3) to see if it reflects a 40% savings.
No luck. It still only show the 39.97% savings, and 8 points acheived (instead of 11). I just realized I posted this in the wrong rating system-this is actually a CI project.
Pre-rinse valve
The project has a pre-rinse valve with a flow rate of 1.27gallons per minute. How do I estimate daily uses and duration?
Thanks!
Note that if your project is registered after 11/01/11 then the pre-rinse spray valve flow rate must be 1.6 gpm or less in order to comply with the prerequisite, and no savings can be claimed for this fixture (as outlined in the Addenda found here https://www.usgbc.org/ShowFile.aspx?DocumentID=10509 ).
If your project was registered before 11/01/11 the pre-rinse spray valve may be included you should provide a narrative and calculations to support a reasonable estimate for the performance values and usage assumptions (duration and uses per day).
Carlie,
The project was registered after and the flow rate is less than 1.6gpm. However, when inputting this on the online form, no total daily uses or duration appear as they do with other fixtures. I was wondering if there is a way to estimate these figures?
Thanks
Correct, there is no default daily usage for the pre-rinse spray valves. You will need provide a narrative and calculations to support a reasonable estimate for the performance values and usage assumptions (duration and uses per day) and enter this data in the form calculations.
Hope helpful!
MD - Since you say that your project registered after the November 1, 2011 Addenda, you can't include the pre-rinse spray valve fixture in the Flow Fixture Table anyways ("no savings can be claimed for this fixture"). Instead, you must only demonstrate that the flow rate is less than the 1.6gpm maximum limit. You are not allowed to estimate the usage rates in as you registered after that particular Addenda was posted.
To demonstrate compliance, there are two ways to handle this:
1) If you have form version v4.0 or later for WEp1, you should be putting the flow rate for the pre-rinse spray valve in the separate pre-rinse spray valve section which follows after the Flow Fixture Table. That section has the question asking whether the project includes pre-rinse spray valves or not. When you select yes, a new field appears asking you to input the highest flow rate for the valves in the project.
2) If you have form version 3.0 or earlier for WEp1, you should not include the pre-rinse spray valve in the Flow Fixture Table. Again, as your project registered after that particular Addenda, you're not allowed to claim any water savings for the pre-rinse fixture. Instead, I would recommend writing up a supplemental narrative and uploading it under the special circumstances section which includes information regarding the manufacturer, model number, and flow rate for that pre-rinse spray valves to clearly highlight that it is below the 1.6gpm maximum. That would allow you to demonstrate compliance without having to go through the forms upgrade process.Requesting an upgrade to the most recent form is always an option if you don't want to do the supplemental narrative route.
Hope that clarifies how you would need to include your pre-rinse spray valve for this project as it was registered after the November 1, 2011 Addenda. It can be a little confusing if you are looking at an older version of the form.
Carlie, Kristina, thanks!
On another note, if we are including toilets for disabled occupants that have different flush rates but we cannot obviously know how many occupants will be there to use them, is there a way of estimating this number or should I just put the number of occupants the same as the number of toilets we will be installing (38 disabled toilets)?
Three Different Kitchen Sinks
If our project has three different kitchen sinks with varying flow rates (ie SK-1: 1.0GPM, SK-2: 1.5GPM etc), how do I enter the usage for the 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. in the project? LEED indicates 1 daily use for each FTE but I am unsure if I should include all 3 sinks in the calculations and divide the number of FTE by 3 or say each FTE uses all three sinks in one day.
It wouldn't be appropriate to assume that every 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. uses all three sinks in one day. You probably have 2 options to move forward:
1) Least Work --- include only the kitchen sink with the highest flow rate in your calculations. This will hurt your overall water reduction savings as you will be conserving the least amount of water for each use, but is the most conservative estimate. Any changes to break out the uses between the various fixtures would only help your overall reduction, so it would probably be awarded. If using this option, I would include a note in the Special Circumstances box of the form saying that you're electing to only include the highest flow rate for ease of calculations and that any inclusion of the other fixtures would only help, not hurt, your claimed overall reductions.
2) Most Realistic --- include all three kitchen sinks in the calculations. To do this, you would need to take the overall Total Daily Uses for that fixture and divide it amongst the three different sinks. You would need to develop some reasonable methodology for dividing the overall Total Daily Uses that works for your particular project. For example, if you had 100 FTE, you'd have a total of 100 Daily Uses to be split between all of the three collective kitchen sinks. If one sink is in the main break room, one is at a small coffee station near reception, and one is near the meeting rooms, it might be reasonable to assume that the majority of occupants will use the main break room (50?), followed by the coffee station sink (30?), and then the meeting room sink (remaining 20?). That's just a very rough example w/o of your project details. You definitely would need to form your own breakdown based on how your project operates/is setup.
For this option, you'd just need to come up with a logical method for your particular project to breakdown the uses. It could be evenly split - it all depends on the nature of your project/how you think they'll be used. You definitely need to include a supplemental narrative to explain how you got to that breakdown for the reviewers. When you are inputting the data into the WEp1 Form, you will need to uncheck the "Default" box next to each of the kitchen sink fixtures. That makes the Total Daily Uses column editable for the fixture so that you can input your own number for that particular fixture. In breaking out the uses between the same fixture, just make sure that that total for all of those collective kitchen sinks adds up to the LEED default for the overall Total Daily Uses for that fixture (in the example above, you want the total to equal 100 as you have 100 FTE x 1 kitchen sink use/day).
Option 2 really isn't that difficult for kitchen sink fixtures once you understand how to easily put it into the WEp1 Form. It will definitely get you the most accurate overall reduction as you'll be getting the extra water savings from those lower-flow sinks. Hope that helps!
Clogging Issues with Low Flow Fixtures
We installed low flow toilets throughout our newly constructed 1.3 million square foot building and now experience line clogging issues. We still believe the installation of the fixtures was the right thing to do but need a solution to get additional pressure into our lines without adding huge additional costs, as we have over 70 toilets in the building. With only a portion of the building occupied, we have already incurred costs to have clogged lines flushed out. Any advice on a resolution would be appreciated.
WE Pr 1 lavatory faucet durations
Our reviewer has noted in the technical advice that "for projects registered after Feb 2, 2011, a 30 second duration is required for lavatory faucets." We have used either 15 seconds, or 12 seconds on other projects registered after this date with no issue. I can't find where this is coming from, and they did not reference any particular addenda. Anyone know?
Never mind. I just found it! We can still use the 15 and 12 for autocontrol. Thanks.
Wash Fountains not meeting .5 gpm baseline.
Unless USGBC has a different interpretation with regards to wash fountains , we may not be able to get points on water conservation because the wash fountains (Bldg 3) uses 3 gpm. The baseline for commercial lavatory is 0.5 gpm with 20% required reduction of 0.4 gpm. Can anybody comment on this scenario. Do we need to separate the wash fountains to meet the criteria?
When you say "wash fountains" what exactly are you referring to? Are these the lavatories in the bathrooms for hand washing after people use the bathroom? Or are they for something else?
I had a residential LEED-NC project include a circular washfountain in one of the amenity spaces (outside of their fitness facility) and came up with a calculation method that was accepted by the reviewers.
In my situation, the installed washfountain had a flow rate of 1.25gpm but was designed for 5 users to wash their hands at once. I took into consideration that 5 users, realistically, would not be using the fixture every time but 2 users at a time was a more conservative assumption. Therefore I was able to divide the flow rate by 2 and use 0.625gpm rather than 1.25gpm. Its still above the baseline, but much better. The reviewers accepted this method (with a thorough narrative explaining the situation) and approved the prerequisite/credit. Since it isn't a typical lav faucet, I'm not sure it was even necessary to include but I'd always rather be safe than sorry, especially with prerequisites. Good luck!
Keep in mind when specifying washfountains that different activation controls are available - some have individual station controls with sensors or pushbuttons for each user, with 0.5 gpm flow rates at each spray head. In that case I treat each station as a public lavatory.
WE p1 for Commercial Interiors Retail - Process Water Use
Hi every one:
I am working in a project in Chile, it is a Foodmarket located within a Mall which is also pursuing LEED Certification. This Foodmarket considers Ice Machines and other Commercial equipment which must be included in calculations to demonstrate pre-requisite's compliance. It is the first time for me doing this calculations and though I downloaded from leedonline an active form sample I do not know how to carry out these calculations for 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. savings as I can't figger out which means ADO (it appears in the form and I don't know what it means and obviously how to obtain this number) and the last Water Use Guide has no content regarding to this item. Does any one has any example or guide that can provide me in order to clarify how calculations must be done?. I am very confused about all the numbers I have to introduce in the form. Please help me......
Hi Maria
I recently faced the same challenge and had to figure out how to document the ice machines, dishwashers etc. However, my project was NC retail so I'm not sure if there are some differences in the forms. If you want me to email you my calculations and the data I used I'm happy to do so. I find that easier than trying to explain every step on this page.
Best Regards,
Helena Skanska Sweden
Dear Helena:
You can't imagine how happy made me your reply. I will be more than grateful to receive any help you can provide me. I agree than calculations themselves may be more instructive than explain all step by step with narratives. My e mail is ma.fda.a@gmail.com or fernanda.aguirre@edificioverde.com. Thanks so much. Will be in touch.....
Best regards,
María Fernanda Aguirre
Metering Faucets - why the "standard" requirement/limitation?
There's been a lot of talk recently about the auto-control / metering faucet requirement in LEED via the "Water Use Reduction Additional Guidance" document. I understand the requirements per the document (and the 12 second allotment for autocontrols going back to the earliest versions of LEED), but I'm hoping someone can help me understand why both the low-tech "push button" type metering faucets as well as the high-tech "auto-sensor" faucets that are only on when your hands are under them are now grouped together under "metering."
It seems to me that these two types of "metering faucets" are very different. In the first case with the low-tech "push button" type, where the user pushes a button and the water is on for a specific amount of time until the metering fixture turns it off, there is always a set amount of water being used. If the user feels that one "push" isn't enough, they have to push it again and the water will continue running until the end of the cycle -- whether or not the user needs it that full amount of time. With the “auto-sensor” faucets there are also two types – those that once triggered act just like the “push button” type and stay on until the time runs out, and the high-tech version that are only on when they sense hands underneath them. For the later case, if the faucets are only on when hands are underneath them, they will be saving more water than the ones that are on for a set amount of time.
I understand that 12 sec is the “minimum allowed for good handwashing,” but it seems to me that there should still be a further differentiation between metering faucets that use a set amount of water every time and high-tech faucets that really only use water when demanded. I would think the high-tech faucets use less water than any other type of faucet, metering or otherwise, and should be recognized in LEED accordingly.
With the battery sensor faucets could they / should they be considered in the LEED template using their GPM figure rather than GPC? the auto sensor taps typically run so long as their is movement in front of the sensor. Moving your hands away is pretty much the same as manually shutting the faucet off rather than the automatic push down button.
Also with the flow rates in BREEAMBuilding Research Establishment Environmental Assessment Method, the first widely used green building rating system, developed in the U.K. in the early 1990s, currently used primarily in the U.K. and in Hong Kong. we use a 2/3rds of the flow rate figure for a normal tap based on the fact that people will not typically turn the faucet on fully when hand washing. Any possible justification for this in LEED?
I absolutely agree with you on the inappropriatene grouping of automatic sensor faucets with metered faucets and then applying reduced duration time to both. In researching and documenting this credit for a few projects in LEED v2 and LEED 2009 I've found the following four types of faucets which are not accurately reflected in the LEED form calculations.
Sensor activated, variable duration per user (runs until user removes hands)
Sensor activated, metered output (starts running when it senses a user, then runs for a preset amount of time or flow quantity)
Manual activated, metered output (pushbutton, run for preset amount of time or flow quantity)
Manual activated, variable duration per user (i.e. regular leverset faucet)
LEED Users note that 12 seconds is NOT the recommended time for hand washing and shouldn't be used as an ideal duration of use setting for any kind of faucet.
The US centers for disease control recommends 20 seconds for good handwashing practice.
http://www.cdc.gov/handwashing/
For history on the length of duration see the LEED v2 Reference Guide, Credit 3, Calculations example p104 "Occupants in this example are assumed to use lavatories for each restroom use for 15 seconds", then later in example on p105 "Motion sensors and electronic controls are used on lavatories, sinks, and water closets. These devices are estimated to reduce lavatory and sink use duration by 20% but do not reduce the flow of water closets. These fixtures' duration data have been correspondingly adjusted form 15 seconds to 12 seconds."
The shortcut to combine faucet types and reduced duration multipliers in the programming of the LEED form was not a good move.
Applicable version of water use reduction additional guidance
I've seen several versions of this question posted, none of which appears to have been answered, so I'll ask it again.
What version of the water use redcuction additional guidance should be applied?
The project I'm currently evaluating was registered on 1/23/12, but the leedonline credit resources list version 7, dated July of 2012 as the applicable version. Is that going to continue to change until the project is certified?
If I wanted to argue that we met the version in place on 1/23/12, how would I find past versions of the document to support that case? I'm not sure the answer is going to help me, but I think it's a valid question that needs to be answered.
During a recent review, a project's WEp1 was marked pending because I hadn't followed the most recent version of the guidance document (which was released AFTER I submitted for review) so I wrote in to the GBCI to see what version we were actually required to use. In the response I received, they stated "Please note that this document is not bound by project registration date and project teams should be following the guidance that is current at the time of documentation submittal."
So I guess teams should check for any updated versions immediately prior to submitting for review and update water use calculations as needed. Now if only they announced when the updates were released...
Hi Carly,
Well that's the first time I've seen a reviewer put it in writing that the document is not bound by the registration date, but I can't say I'm surprised. Despite the profusion of resources, guidance, addenda, rating systems, credit forms and LEED Interpretations, we have seen a continuing erosion of that boundary line of project registration date. How to keep up with the requirements is something even reviewers are apparently struggling with given the comments we're seeing.
There's always a natural bit of reviewer bias in that they all seem to look to each other for cues about what is required and to what degree, rather than to the documentation requirements in place at the time. It's obviously a difficult task.
GBCI is still maturing and I expect there will be challenges they struggle to meet. But this is a critical issue to future growth. We all need to be able to rely on knowing what the LEED requirements are for a project at any given time. And everyone needs to be able to trust that a LEED certification offers some apples to apples benefit in assessing green buildings, not just added cost, frustration and paperwork as a reward for doing the right thing.
Here's hoping they get a handle on this issue, perhaps in v4.0.
Thank-you Carly and Michelle.
GBCI provided the following response to my question, but I still cannot comprehend how a guidance document can be applied, with changes, until the point at which the project is submitted.
"The Water Use Reduction Additional Guidance document is a supplement to the WEp1 prerequisite form, and provides clarification of how to use the form to implement the existing requirements. Therefore, the guidance document is not bound by project registration date. You should use the guidance that is current at the time of project submission."
I'm curious, what is the specific issue you're grappling with, and how have changes to the guidance document affected how you document it, and comply with the prerequisite requirements?
Tristan,
The issue we're addressing is the 12 second limitation on metered lavatory faucets. Our design case uses 10 second faucets, which appear to have been eliminated in an addendum. The issue came to light through the additional guidance document, but it took a bit to find where the 12 second reference came from.
To the best of my knowledge, that wasn't an original criteria in LEED 2009. The addendum wouldn't apply to projects registered before that, so how can the same information be applied to all projects through the additional guidance document?
I'm not a plumbing engineer by training, so if my research is off, I'd appreciate more feedback. I've been reading a lot of material to figure this out.
Thanks
I had the same situation with a 10 second metering faucet being specified for my project. We had to resubmit clarifications using the 12-second run time so our overall savings dropped with the revisions, and essentially we had to claim a higher volume of water than will actually be installed. I have been working on LEED projects/water calcs for years so I had never even opened the Guidance Document until the reviewer referenced it in the review comments.
It would be a useful if the document could at least be retitled to 'Water Use Reduction Additional Requirements' or be included as an addenda so it is clear that the document MUST be used. Calling it a guidance document is misleading.
Morning TIffany,
I can understand your frustration. GBCI has already had to acknowledge that you need to look at online credit forms to get a complete understanding of LEED requirements and that these forms change at any time. So I have to agree that they are making a specious distinction when they say the guidance only applies to how to use the form. I have had to resort to that Additional Guidance document numerous times to be able to make the calculations properly.
Construction projects take a while and decisions are literally set in stone at a certain point. Requirements that change in mid-stream are onerous and unfair, particularly when there are supposed to be understood safeguards like project registration date in place to keep everyone on the same page until certification is complete.
The reality is that LEED requirements can be a bit of a moving target, and reviewers sometimes make mistakes about how to interpret their application or their timing with respect to your specific project. Over the years, we've found that it's wise to have a point buffer to hedge against surprises.
However, if you have a good case and a well founded argument you can make, it's possible to successfully contest unfortunate review comments. Intent is still an important part of the picture, not just how you fill out the credit forms. And though I think it would be difficult to arm yourself with previous versions of the guidance, you are on the right track in that context is very important in any conversation with LEED reviewers.
If your isse is not prerequisite compliance, build in a margin of error against the goal you need if you can and hope for the best. If you do have a concern about prerequisite compliance, it might be wise to consider 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 LI to establish your situation.
The 12 second default was put in place as of an 11/2/2009 addendum.
Was your project registered before or after that?
The default value has always been listed as 12 seconds in the reference guide, so the 12 second value stated in the 2009 addenda wasn't an update, it was just a breakout of residential vs. nonresidential. Page 171 of the reference guide states "Table 2 provides default fixture use values for different occupancy types. These values should be used in the calculations for this credit unless special circumstances warrant modifications." Additionally on page 173, it states "The design case must use the rated flow rates and flush volumes for installed plumbing fixtures and fittings." The addenda you referenced does not change requirements for using defaults.
The only document that states the 12 second default must be used in lieu of actual installed metering faucet run times is the Guidance Document.
Hi all,
I agree with Carly on this one. We ran afoul of this issue on several CI projects where we thought we had to get the subcontractors to change all the factory default settings of metered faucets onsite so that we could get down to 10 seconds when GPC became the calculation in V3.0. Then they finally clarified that 12 sec was the minimum allowed for good handwashing.
Thank-you all for the suggestions and comments.
Michelle, I couldn't agree with you more on the need for a good cushion of points. I'm always pushing for more cushion going into the review. In this particular case, the project is working toward Platinum, so there are just fewer extras available.
This has been a lively discussion! I wanted to address a couple of the comments and hopefully help to clarify things:
1. Lavatory installation: Some commenters have expressed concern that USGBC is requiring autocontrol faucetsAutocontrol faucets have automatic fixture sensors or metering controls. to be set to exactly 12 second durations and to switch out the faucets if exactly 12 seconds cannot be achieved – this is not the case. Projects may select faucets with cycles of any duration, and may set those faucets as they see fit. The 12 second design case duration used in the form is meant to represent a typical hand washing duration. According to many sources, durations as long as 20-30 seconds are recommended to prevent the spread of germs (CDC says 20 seconds). Occupant behavior is the hardest variable to control for here. If faucet flow is set to a very short intervals, users will typically reactivate the faucet multiple times, thus negating any savings from the shorter setting. To address this, when documenting these fixtures, projects should use a 12 second design case duration in the form, which allows projects to earn some savings for autocontrol faucets, but not for the durations where users are likely to reactivate in order to fully wash their hands.
2. Precedent for 12 second design case duration within the reference guide: The default 12 second design case duration for autocontrol lavatory faucets is outlined in Table 2 Default Fixture Uses, by Occupant Type on page 171 of the LEED Reference Guide for Green Building Design and Construction, 2009 First Edition. Table 2 outlines the default usage assumptions (uses per day and duration) that are used to calculate the quantity of water use in the baseline and design case calculations. The default values in Table 2 should be used in the calculations unless special circumstances warrant modifications per page 171 of the Reference Guide. This was further clarified with addenda. The reference guide also says that manufacturer flush and flow rates should be used, but not duration of flow.
3. Use of the Water Use Reduction Additional Guidance (WURAG)) – This guidance document was originally created to address questions project teams encountered when completing the WEp1/c3 form. The calculations in this form are fairly complex and are generally not addressed in the reference guide. The WURAG is intended to guide the user through the process of filling out the form, but is not intended to create any new requirements. Unlike 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. and addenda, it does not have an “effective on” date because the guidance is intended for all projects to use, regardless of registration date. It is accessible in the link above, or under the resources tab of WEp1 & WEc3 in the credit library. Wherever possible going forward we will try to put guidance directly in the form for clarity, but this guidance can be helpful for specific project scenarios and it has historically been a faster way for use to deliver guidance to project teams.
I don’t expect this to answer all questions, but I hope it helps to clarify a few things.
auto-shutoff faucets
I am sure this has been answered elsewhere in this listing but I am confused by the back and forth about auto-shutoff faucets, the most common commercial lavatory faucet in much of the work I am involved in. My understanding is the latest guidance is that these faucets should be entered as a metering faucet, with the GPM factored into a 12 second duration, and the baseline would be a 15 second cycle at 0.5 GPM. Is this correct? (Addendum 100000753, Table 2A in Addendum from 11/2/2009 for BD+C). Thanks!
Hi Jonathan,
Yes. Consult your Water Use Reduction Additional Guidance document. For commercial use, the calc generally comes out as 0.1 gpc. Please note the example in the guidance doc uses a 1.0 gpm baseline rather than 0.5 gpm.
How to document a pre-rinse spray valve in the form online????
Review comments have requested that I include the pre-rinse spray valve in the hotel kitchen in my water usage calculations. However, I do not see a category for this fixture type in the Fixture Family pull down menu of Table WEp1-4.
Any thoughts on how the reviewers would like to see me document this fixture?
Hi Robert,
It depends on what version of the WEp1 Form you are utilizing.
The LEED Reference Guide for Green Building Design and Construction, 2009 Edition (Updated June 2010) 11/1/2011 Addenda 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.
Older Forms do show pre-rinse spray valves in Table WEp1-4. Updated forms (after the above referenced Addenda) show a check box asking if pre-rise spray valves are included in the project, and if so, confirming that they are 1.6 gpm or less.
Hope helpful!
Help with a new study of green water technologies!
The Water Research Foundation and Virginia Tech have partnered for a study on the unanticipated consequences of green water technologies and practices on water use in buildings. They need your help!
The first step in this study is a brief internet survey asking about the experiences of experienced green building professionals. Please follow the link below to details and the survey: https://virginiatech.qualtrics.com/SE/?SID=SV_b1uShkZoKVBQcnP
Back of House Employee Breakroom
We are working on a hotel project and I have one question regarding the fixture family classification for faucets. How should the back of house restroom associated with the employee breakroom be classified--public lavatory faucet or private lavatory faucet?
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