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.
Clearly defining Fixture Usage Groups is an important step in achieving this credit. In buildings with toilet facilities that are not accessible to visitors, it is reasonable to exclude visitor numbers from the Fixture Usage Groups. The occupancy values entered in the PI forms should inform, but not necessarily parallel the numbers used for this credit.
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.
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 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. [Europe ACP: Water Use Baseline]
The following fixtures, fittings and appliances are outside the scope of the water use reduction calculation:
Projects in Europe may use the values defined by European Standards.
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 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.)
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 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:
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'm hoping to run by our approach to achieving WEp1 by some experienced LEED APs in the hope to reassuring myself that our approach is acceptable before submitting to USGBC at appeal. Excuse the ignorance- LEED is pretty new to us!
We've had this credit knocked back by the USGBC previously partly due to incorrectly defining Fixture Groups. I now understand that Fixture Groups should be defined by the facilities which the group has access to. As such I believe we should have 2 groups (football academy)- footballers/staff and visitors (transients). On this basis, I have created 2 tabs within the Water Use Reduction Calculator.
On each of the two tabs in the Water Use Reduction Calculator we intend to complete the Flush and Flow tables with details of the fittings installed. There is a requirement to enter the percentage of occupants with access to the fixture. Is this percentage of users within that User Group, or total building users (i.e. all tabs)? I'm concerned about double counting.
Other than that the Calculator tool seems fairly straightforward and a good means of demonstrating compliance I hope!
If anyone with experience of this credit is able to comment on our approach it would be much appreciated!
Susie, I'm going to answer off the cuff without looking at the form, but my memory is that the % is within that user group.
I think if you play around with the numbers in the calculator, you'll see them change in ways that will also confirm your approach.
Since the default assumption is that 100% of male occupants will use a restroom with a urinal, how do you calculate the usage when there is a family toilet (without a urinal) next to the large gang restroom? My guess is that a certain % of the male (and female) population is assumed to use the family toilet in lieu of the gang restroom. However, what would that percentage be? Any ideas of where I could derive an idea of that percentage?
Although the family toilet is ADA accessible, there is also an ADA toilet stall in each of the gang restrooms, so I can't use the ADA calculation to determine the % of people requiring the usage of the family toilet. Any guidance/ideas would be appreciated! Thanks.
when I have an addition project do I have to demonstrate compliance for the new addition and renovated areas or does it have to be applied to all areas? (existing to remain, renovated and new) We are creating an addition that is around 30% of the existing area including a few restrooms, but most of the restrooms are in the existing to remain area. Since only the new area will include high efficiency fixtures Im not sure if we will be able to meet the 20% efficiency requirement.
Catalina, if the LEED project is the whole space and not just the addition, then you have to demonstrate compliance for the whole space, as with all LEED-NC credits.
Ours is a campus project where FTEs from a number of buildings have access to showers and lockers in a separate "clubhouse" building. The clubhouse has a much lower staff number than the other buildings. How do we account for the "visitors" use of the showers? Are they transients? Part-time occupants - just for the 20 minutes they are in the locker rooms?
(I posted this question on the EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating systems. page as well.)
I have just come across the Water Use Reduction Calculator tool in the credit tools for WEp1. Do most people use this to demonstrate compliance? It looks to make the WEp1 process a lot more straight forward...
The instructions say to complete the Water Use Reduction Calculator, upload to LEED Online, and complete any related summary fields in the LEED credit form with results from the calculator. I can't see which are "summary fields" though- can I avoid completing the WEp1 credit form in its entirety if I upload the Water Use Reduction Calculator?
No the form still needs to be completed, the calculator is supporting documentation. I think once you complete the calculator, you'll find the form fairly simple to complete; but do let me know if you need a help.
I've realised that the Water Use Reduction Calculator tool is password protected. This seems a bit odd since it is meant to be a useful resource. How do I go about unlocking it for use?
Additionally, I was wondering if anyone has an example of a completed credit form they would be willing to share with me for a project with more than one Fixture Groups? We're new to the LEED process and would like the peace of mind of checking our approach against that of another project before submitting to USGBC!
I have noticed a discrepency between the default duration shown within the LEED NC 2009 manual WEp1 table 2 and the default duration which auto populates for Private Lavatory Faucet on LEED Online Table WEp1-4:
LEED manual: duration = 15 seconds (12 seconds with autocontrol)
LEED Online: duration = 30 seconds.
Which one can I assume to be correct? I am guessing that there has been an addendum to WEp1 in the manual that I have perhaps missed...?
There was a addendum to Table 2a in 2011:
"In the sixth row (“Lavatory Faucet”), replace the duration (sec) of 15 with 30; replace the related note below table with “Default duration for the metering type / autocontrol faucet is 15 seconds for the baseline and 12 seconds for the design case."
Thank you very much Charles.
Excuse the LEED ignorance (its a fairly new one on us here in the UK) but is there a complete list of addendums to LEED 2009 anywhere? Or better still, is there an updated LEED manual which includes all of the addendums? I'm concerned as to which other addendums I may not be aware of!
No problem, we're all here to help each other. )
Addenda tracking in v2009 is a bit disorganized, always best to go the the USGBC website and check the "credit library" for the current language. There are also some pdfs summaries you can download that show the various changes at: http://www.usgbc.org/search/document%20addenda
Just scroll down until you see the document for rating system you're working with; careful, there are also updated addenda summaries, so make sure you scan them all to get the most current.
The USGBC is improving this addendum tracking process for LEED v4.
Our project is the back stage area of a seasonal outdoor amphitheater concert venue. The venue hosts concerts 35 days per year over a 24 week period. There are three types of occupants: Type 1: 2 permanent full-time venue staff members that work 40 hour weeks rear round; Type 2: ~25 seasonal, part-time venue employees that typically work 16 hours per day on show days only; Type 3: ~70 traveling production staff and artists that arrive only on show days and typically work 12 hours on those days only then leave. Calculating each group as FTEs the annual usage is 17 FTEs. Peak occupancy on show days is 97. Has anyone had experience balancing this type of occupancy between Site Credits and Water Efficiency credits in NC 2009? I have chosen to calculate the traveling production staff as FTEs rather than transients. I should add that it will likely also include a narrative explaining that the ~70 production staff/artists will arrive for the day by tour bus and will not be biking, taking public transit, or driving/parking personal vehicles. The venue does have a 500 gallon biodiesel tank to fill tour busses. The audience area is outside the boundary for this phase of the project. I'd appreciate any insight. Thanks!
We are considering using multi-flow shower heads on a commercial office project for the locker rooms. The shower heads can be adjusted by the user to flow between 0.5-1.5gpm depending on the nozzle selected for the desired task. What would we be able to claim as the flow rate if when installed we set them 0.5gpm? In order to achieve the additional point for this credit we need to have the shower have at least a 1.0gpm flow rate.
You'll have to use the worst case scenario for your water calcs (i.e. the highest water flow rate that can come out).
You could, however, add a flow reducer in to the pipe to limit the water coming out of the pipe and going in to the showerhead to be 1.0 gpm. (I've come across them in various rental houses in California.) Since the showerhead is designed to work at a lower flow rate, hopefully the user experience won't be too negatively impacted by that. Or you could use a different showerhead. (I know Bricor makes some that are lower flow rates, incl. handheld options...)
We have a hotel where some rooms have both, showerheads and baths. One showerhead placed overhead in the bathroom, and the bath placed in the middle of the room. They have different flow-data. According to BD+C Reference Guide, the calculations for WEp1 only include the following fixtures and fittings (as applicable to the project scope): water closets, urinals, lavatory faucets, showers, kitchen sink faucets and pre-rinse spray valves. Should I consider baths?
In case I should, bath will be used much less than showerheads, and if bath is used, shower won't, but we do not know how much each of them will be used. Which flow data shall we use? The highest flow or the average flow, or?
Thanks a lot
Do you mean you have a separate shower and a separate bathtub with no showerhead?
If the bathtub does not have a showerhead, it's exempt from the calculations because the purpose of the faucet in the bathtub is to fill the bathtub to the amount desired, and not related to amount of time someone is using it.
If the bathtub does have a showerhead, it will need to be included in the calcs. I would then recommend doing a separate user groups/fixture groups -- one for people using the shower and one for people using the bathtub's shower. Include a narrative explaining how the bathtub is estimated to be used X% amount of the time and the shower is expected to be used (100-X%) amount of time. And then you multiply the total users by X% to assign some to showers and some to the bathtub. (Note: There is a chance the LEED Reviewer could require you to assume all the people, since they have access to both, would use the worst case scenario all the time, but I'd make the argument and wait to see if that's what they say.)
We have a hotel where the showers have two showerheads. One showerhead placed overhead and one han-held showerhead. They have different flow-data.
Both showerheads will be used, but we do not know how much each of the showerheads will be used.
Which flow data shall we use? The highest flow or the average flow, or?
I believe you need to use the worst-case scenario (the highest flow rate). Along those lines, if they can be used simultaneously, I believe you'll need to add the two rates together...
From what I can tell coffee room water fixtures (used for washing coffee cups and hands) in open office spaces are to be included in the credit.
What is the baseline flow rate for this fixture ? Is it 2.2 gpm (8.5 lpm) or 0.5 gpm (2.0 lpm)?
You would use "Kitchen Sink" as the fixture family in Table WEp1-4, which has a baseline of 2.2 gpm
I was wondering if fixtures at patient rooms can be classified as residential or private? given that it is a public institution, I'm guessing it would gear more towards "private" but this would apply only to lavatories, what about water closets and showers?
There was an addenda last fall (Oct. 2014) that hopefully clarifies it for you - Addenda ID#100001966 :
"For healthcare projects, ... Lavatories in hospital inpatient bathrooms and inpatient rooms are considered private. The inpatient lavatory and water closet should use the default residential usage assumptions (of five times per day per residential occupant), unless specific project conditions warrant an alternative. Lavatories in hospital inpatient rooms (outside the bathrooms) are considered private if used by patients and/or staff similarly to a residential lavatory, or can be exempt if they are used by staff primarily for medical or clinical use..."
The LI Michelle correctly brings up is based on the assumption that these patient rooms are private sleep rooms. Rehab facilities often have semi-private sleep rooms. Since we don't know your floor plan, I thought this was pertinent to this conversation.
Thanks, it is very helpful information. We have 2 rooms (with 2 patients each) that are served by one joined bathroom (Water closet, lavatory and shower). The 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 is very explicit, however they don't mention showerheads. Since these are a big water consumers could you clarify? Thanks
i would say that the shared bathroom is public and that the shower head counts in the calculation. It is a regulated fixture.
I don't know, but my gut would say the shared bathrooms are still "used by patients ... similarly to a residential" bathroom and should therefore be calculated based on residential usage. And I would assume the showers would be used the same as the toilets and bathroom sink -- i.e. residential usage. But that's just what my gut says. I think it really depends on how it's being used. Is this similar to the bathroom that the Brandy Bunch had -- you know one bathroom in between two bedrooms like in a house? Are the patients "living" in these bedrooms that the bathroom is connected to? Do the usage patterns listed in the LEED Ref. Guide seem like they are appropriate or inappropriate for how they'll be used?
That said, if they are considered public, the water calculations will allow for a lot less water (particularly on the lav), which would be your worst case calculations, so assuming that for the calculations would be "safer."
Personally, with my limited knowledge of how they're being used, I'd probably try to make the argument that they're residential (assuming the people using them are "living" there for multiple nights in a row) and cross my fingers...
[Sorry, Internet Explorer gave me problems and apparently posted twice even though it looked like it didn't post at all. Hopefully someone "official" can delete this comment?!?!?!]
We have a NC-2009 project were there is an automotive service area that has a washfountain for use by the mechanics only. They also have a locker room area with toilets, urinals, lav's, and showers. Should the washfountain be 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.' because it is used for operational processes and not covered by EPAct 1992 or should it be included in the WEP1 calculations? Thank you!
You may want to review the conversations about commercial kitchens on this board. I believe the practice there has been to have the hand wash sinks align with LEED WEp1.
What is the documented proof required to be submitted to USGBC confirming on the Occupancy considered for our project. Will a letter from the client confirming on 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., while assumptions on the transients suffice, or do we need to provide furniture layouts showing the seating arrangements? Also, in cases where furniture layouts are unavailable how can this be addressed?
Appendix 1 of the Reference guide says: "Projects that know the tenant occupancy must use the actual numbers, as long as the gross square foot per employee is not greater than that in the default occupancy count table. If code requirements required gross square foot per occupant is less than
those in the table, this is also acceptable." So as long as your occupancy numbers meet these requirements, no other documentation should be needed. As far as transients, include a narrative explaining your assumptions, and you should be ok.
Hi, I am working on an office building and the team is considering to include a car wash bayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession.. Would I be able to classify this as 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 exclude it from the WEp1 calculation?
Correct. Since car washes are not regulated by the Energy Policy Act of 1992, it is excluded from the WEp1/WEc3 Indoor Water Use Reduction calculations.
Michelle, thank you for the quick response!
I have received my second metered lav faucet submittal with less than 12 sec from factory duration. This American Standard faucet is a 0.35 gpm faucet that is factory set for 7.5 seconds for a 0.044 gpc. I am aware that LEED does not permit a duration less than 12 secs in the metered faucet calcs because they don't believe that hands can be washed effectively in less than 12 seconds.
Obviously I can do the calc with 12 secs despite the duration noted, but my concern is that the faucet itself may be rejected for the shorter preset duration. Am I supposed to reject this faucet or have it manually reset to a longer duration because it's too much water reduction?
That's an interesting question. Yes, LEED requires you do the calcs and determine the gpc based on 12 seconds, but obviously with a factory pre-set of 7.5, if it's activated twice, for a thorough hand washing, that would be 15 seconds. The reality is that it will average out over time: some 7.5 sec, some 15 sec, some 0 seconds. Just enter the value based on a 12 second cycle and you'll be fine.
I agree that is probably what the answer will be, but I find the issue interesting because it is a conflict of imperatives - water reduction vs. "effective handwashing duration". When this duration cap was originally set, it appeared to be within a context of people trying to game the calcs for points. And that made sense, despite the somewhat arbitrary seeming number 12.
But now the industry has responded with even lower fixture durations and this approach disincentivizes water reduction below a certain level. While I don't disagree with your comment about activating it twice and averaging, that could also be said of all the low flush fixtures, particularly dual flush, and we are not obliged to overstate their use.
Michelle, I agree; whether or not LEED guidelines accurately predict individual behavior is difficult to say. I would assume as more actual water usage data is collected from certified projects and compared to the predicted performance, the guidelines will be refined. My gut feeling is the current limits probably overstate water usage in most public/office restrooms.
The installation time limit doesn't matter for LEED. In LEED theory, if the setting is 5 seconds, the user will switch the faucet on enough times to reach the 12 second limit.
FYI, answer as expected is "Projects should use a 12 second design case duration for LEED calc purposes, which allows projects to earn some savings for autocontrol faucetsAutocontrol faucets have automatic fixture sensors or metering controls., but not for the durations where users are likely to reactivate in order to fully wash their hands. As such projects may select faucets with cycles of any duration, and may set those faucets as they see fit".
Interesting. Does the faucet have a proximity sensor, or is it simply on for 7.5 seconds, then off`? I have had success with faucets pre-set to turn off after 6 seconds, once hands are removed from the "active range".
We are working on an industrial facility project were the wastewater treatment plant is offsite the project. The project is located in an industrial complex with the necessary infrastructure for treating wastewater.
The water will be send to the treatment plant (we have a signed contract between the owner and the industrial complex administration), and then the local government will supply the treated water, since the government runs the plant for the treated water supply (we also have the signed contract between the owner and the local government).
Is this a feasible way for obtaining the pre-requisite WEp1 and the credit WEc3? because, reading the document WEp1 Additional Guidance, the document indicates:
"Sources of 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. that do not apply to the Water Use Reduction prerequisite and credit include: municipally treated wastewater...."
In this case the wastewater from the project will be send to the treatment plant in order to obtain treated water supply by using the existing infrastructure in the area.
Thank you in advance,
is there a definition for transients versus retail?
We have a dining hall and aren't sure how to classify the students who enter the building for meals.
The definition for Transient users in the reference guide isn't helpful...
Students using a dining hall would be considered "transients". You just need to estimate the number of total of "student hours" the hall is used and then divide by 8 hours per day to determine 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.. So for example, 100 students spending an average of 2 hrs/day in the hall would come out to 25 FTE's
that doesn't make sense to me... why would they have different categories in the form if you just convert them to 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. at the end of the day....
It makes a difference as to how the water usage is calculated.
Per the Reference Guide (p171) "Most buildings with students, visitors, and retail customers will also have 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. occupants. Half of all students and visitors are assumed to use a flush fixture and a lavatory faucet in the building and are not expected to use a shower or kitchen sink. A fifth of retail customers are assumed to use a flush and a flow fixture in the building and no shower or kitchen sink."
Because there is more than one way to view something? Personally, I would not have used Charles' method although I do see it as valid. The transient population is variable and their behavior changes throughout the day. The form is allowing you to customize. For example, your students may not make use of the facilities at dinner because they've been to their dorms before hand but they may use them during lunch. If your lunch population is less than your dinner population, then you can adjust the water use in the form instead of making sweeping assumptions that may not be applicable to the individual project.
For the record, I would not have done things the way Charles does not because I feel he is wrong but because our projects have transients that have more predictable behavior which allows us to model more accurately. His way is completely valid.
thanks guys!!! I am going to try to get more info from the owner to see how long these students are expected to dine in the building per day to make the usage as accurate as possible. I'm hoping they are more like retail than transients because our flow fixtures in a residential part of the building are about ~10% more efficient than our dining hall fixtures. I was confused by converting them to 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 form even though the math makes sense. I'd love to get this form approved on the first round of review.
It's also a little hard for us to estimate how many kitchen sink uses will occur in the dorms since the kitchens are very few and far between.
The project I am working on is an office building located in middle east. the Washroom water closets all has water jets or a bun gun fixture for washing purpose instead of using toilet paper. Shall these fixtures be included in WEp1 or WEc3 credits? and if yes under which family group should they be ?
Since these are not regulated by Energy Policy Act they are exempt and are NOT included in the WEp1/WEc3 calcs.
My project was upgraded to the new version of LEED online around the beginning of the year so I am getting used to the new set up (so far it is very nice). Question: My plumbing engineer has said in the past his WEp1 form has been linked to 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. information in PIf3. Is this accurate? I thought the FTE count in PIf3 wasn't specifically "linked" to the WEp1 credit template as the groups could be slightly different. This is a bit complicated as we are pursuing a multiple building certification and are dealing with University dorms with a dining hall so the FTEs are complicated to say the least. Am I correct that there isn't a "link" missing between the PIf3 and the WEp1 template? I really appreciate the help!
your overall numbers in WEp1 should add up to equal the numnbers in PIf3. So if you have 100 dining hall 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 300 visitors and 100 residents that should be the same between WEp1 and PIf3 or your reviewers will point out the discrepancy and deny the credit. You can split them up however the fixture groups work out. So you might have 50 dining hall FTE using one set of fixtures and 50 dining hall FTE using another but if you had a split that didn't add up to 100 FTE you'd have a problem. The WEp1 form lists the data you included in PIf3 but then you set your fixture groups on your own manually. That data at the top of Wep1 is autopopulated from PIf3.
Do sinks in exam rooms need to be included in the calculations? They are primarily used for handwashing. If so, are they entered as 'sinks' or 'lavatories' as the baseline?
In LEED HC, clinical sinks are specifically exempt from the calculation and exam rooms are clinical use fixtures. There are a lot of other healthcare regulations and research about the flow rates on these sinks. If your owner is being fairly pushy about it, you need to accept what they are telling you.
My thoughts are that NC will follow the HC guide on the exempting these sinks and I'm pretty certain it would. There is likely a 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. or LEED Addenda for NC but I don't have it at my fingertips at the moment. Do write in your narrative that you've exempted the sinks due to the clinical nature and the demands of the clinical environment.
Patient bathroom sinks for inpatient rooms are still included but are private.
WEp1 Water Use Reduction addenda, dated 2/2/2011, states that faucets whose usage patterns and flow rates are regulated for medical or industrial purposes are exempt from this calculation. Exam sink fixtures are not covered by the EPAct 1992 standard, Uniform Plumbing Code, or International Plumbing Code, as required by WEp1 requirements, and can skew water use consumption due to not having a standardized code that defines typical daily uses.
There was also an addenda more recently (Oct. 2014) that clarifies it in more detail - Addenda ID#100001966 :
"For healthcare projects, fixtures used for clinical use related to medical procedures, such as surgical scrub sinks and exam rooms sinks, in hospitals and medical office buildings are excluded from the water use calculations. Medication room sinks, utility room sinks, and other exam / procedure / observation room sinks for clinical use are also excluded. Should exam / procedure / observation room sinks be used primarily for hand-washing, they may be included in the water use calculations at the project team’s discretion under the public lavatory category. If included, project teams should provide a narrative explaining the usage assumptions for these sinks. Lavatories in hospital inpatient bathrooms and inpatient rooms are considered private. The inpatient lavatory and water closet should use the default residential usage assumptions (of five times per day per residential occupant), unless specific project conditions warrant an alternative. Lavatories in hospital inpatient rooms (outside the bathrooms) are considered private if used by patients and/or staff similarly to a residential lavatory, or can be exempt if they are used by staff primarily for medical or clinical use.
Nutrition station (pantry) sinks and hospital staff lounge sinks should be included in the water use calculations under the kitchen sink category."
For an existing building undergoing major renovation how should the existing water fixtures be handled as far as WE prerequisite is concerned? Please note that no addition to the building will take place.
Could existing fixtures, if outside the scope of renovation, be excluded from the calculations? If not, because of the lack of technical information about existing features, would measurements be accepted to the BD+C version similarly to the EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating systems. one? Thank you in advance.
Through a series of circumstances, we are in the appeal process to try and meet WEp1. We have determined that we can either spend a significant amount of money to install two additional urinals in ADA single-user bathrooms, or reduce the automatic flow duration on lavatory faucets below the 12 second default. We previously had listed 8 seconds for the duration (and passed), but didn't justify it in our submittal, so the prereq was denied.
Has anyone had success in justifying a duration other than the default on metered faucets? We were considering citing client request and a campus-wide average currently in place to justify it. We don't want to chance this though, as we are already in appeal. Thanks.
I don't have any experience with that getting approved. I'm fairly certain they'd say 12 seconds is required for sufficient hand washing. I would not approve it and it would be very risky to submit. I believe they say this is a major no-no in the principles of LEED webinars. If you want more feedback Toto might have the best info. They had a faucet with a <12 second duration but LEED reviewers wouldn't let the duration be less than 12 seconds in the calcs. They had a good article in EDC magazine but it's no longer posted online. Best of luck.
I would caution using anything below a 12 second duration in your appeal. The USGBC Water Use Additional Guidance states that durations less than this are not permitted for LEED calculations as shorter intervals are insufficient for typical hand washing. The direction of LEED (per v4) is also moving away from giving so much credit (in v2009) to metering faucets.
Thanks for the input Kathryn and Carlie. That's exactly what we needed to know.
Yeah, I've never seen less than 12 seconds approved. (And I've always seen anything less than 12 seconds be questioned and be forced to change back to 12 sec.)
You're already using 0.35 gpm aerators I assume? And dual flush toilets in those bathrooms?
We have seen several comments regarding the possibility (or not) to achieve both WEp1 and WEc3 through the use of on-site greywater and wastewater. We would like to confirm that, in fact, we can calculate the % of water savings by subtracting the on-site reuse of grey and wastewater for toilets and urinals, from the design annual water use as a result of the installed fixtures. A project we are working on cannot achieve a 20% reduction solely from fixtures, but is treating all of its grey and waterwater and reusing it, which means that 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. will only be used for faucets and showers, achieving a water savings of over 50%. The Additional Water Guidance (version 8) states that "projects are allowed to use on-site alternative sources of water to achieve water use reduction through an alternative compliance path". It goes on to say that "examples of on-site non-potable water sources that apply to the Water Use Reduction PREREQUISITE and credit include: greywater, captured rainwater, air conditioning condensate, etc". Because we have seen comments saying that the 20% reduction MUST be achieved through efficient fixtures, we would like to confirm that this is not the case and that, per the Additional Water Guidance, grey and wastewater reuse can in fact be used to achieve the 20% reduction.
If you are treating the grey/wastewater and then re-using it for toilet and urinal flushing, then it counts. If you use for irrigation, it doesn't. "The design case annual water use is determined by totaling the annual volume of each fixture type and subtracting any 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. supply." (LEED Reference Guide for Green Building Design and Construction 2009 Edition)
area you required to treat harvested rainwater when using to flush toilets? if yes, what does "treated" mean exactly, what level of treated would be required? Thanks!
Looking at the Water Use Reduction - Additional Guidance in the section for Dual flush, they say: " For the female water closet usage, there is a 1:2 ratio in terms of number of full-flush to low-flush uses per day. For the male water closet usage, there is a full-flush usage per day." Does this mean that if a visitor female with 0.5 uses/day and male visitor with 0.1 uses/day according to the default fixture uses, then in the average for dual flush the default uses are broken down by the ratio like this?
(0.033 uses/day x full flush rate) + (0.066 uses/day x full flush rate) +
(0.166 uses/day x full flush rate) + (0.332 uses/day x full flush rate)
divided by 0.6 total female & male uses.
Is this assumption correct?
Based on the Water Use Guidance document example you would calculate visitor dual-flushA type of water-saving toilet that gives a choice of flushes depending on the type of waste solid or liquid. uses as:
[(0.1 use/day * 1.6 gpf) + (0.1 use/day * 1.6 gpf) + (0.4 use/day * 1.1 gpf)] / 4 uses/day = 1.27 gpf avg. flow rate (with urinals)
Hope this helps!
Tips and screenshots on LEED Online documentation.
Capturing rainwater for interior use can contribute to WEp1 as well as reducing stormwater quantity.
Capturing rainwater for interior use can contribute to WEp1 as well as reducing stormwater quantity, which can help with improving stormwater quality.
Graywater may be used for landscaping in addition to using it for indoor fixtures.
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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