Our project has made water efficiency a high priority and has elected to install 0.5 GPM flow restrictors with occupancy sensors on all lavatory faucets, waterless urinals and dual flush toilets throughout. In our analysis regarding whether to continue our application under the LEED CI version 2 system or switch over to LEED CI v2009, we were surprised to find out that we would not be able to reach the 30% threshold and would therefore not be able to achieve any points for WEc1 under the version 2009 system, despite the fact that we have selected some of the most efficient fixtures available on the market. Using the fixtures listed above, we are able to achieve 45.9% savings under the v2 system, but only 29% savings under the new system due to the fact the baseline flow rate for lavatories under the v2009 system is 0.5 GPM instead of 2.2 GPM. In essence, the bar is set higher under the new system, but the baseline flow rate for lavatories is also much more stringent, making it near impossible to achieve points under this credit without the use of composting toilets, gray water systems or rainwater systems - which are not allowed by high rise buildings in our area. We have two questions: 1) Given the fact that it will be near impossible for the majority of LEED CI project to achieve points for WEc1 under the v2009 system despite selecting the most efficient fixtures on the market, we'd like to ask the USGBC to reconsider the threshold for achieving points, particularly since the baseline for faucets in v2009 changed significantly. We suggest lowering the first v2009 threshold for points to 25% water savings which would allow projects that use 1/8 gallon, high efficiency urinals to potentially earn points. An alternative solution would be to use the same baseline as version 2, while keeping the raised v2009 threshold at 30% savings. 2) If you are not willing to reconsider the threshold or adjust the baseline for faucets, please advise how we might achieve points for WEc1 under the v2009 system in cases where composting toilets, gray water systems and rain water catchment system are not allowed. Keep in mind we're already using 0.5 GPM flow restrictors and occupancy sensors on all faucets, waterless urinals and dual flush toilets throughout.
The project is requesting the USGBC to revise the thresholds that have been established for the LEED-2009 rating system. The model plumbing codes requires .5 GPM or .25 GPC for public use (See footers of LEED 2009 Design and Construction Reference Guide). Part of the goal of the LEED rating system is to transform the marketplace towards a more sustainable building practice. As the market transforms and old best practices become standard practice, LEED also continues to evolve and raise the bar to continue its mission of transforming the marketplace towards a more sustainable built environment. LEED credits are established through a collaborative and iterative process of many stakeholders, opened for public comment, and balloted and approved by the USGBC member organizations. Those who wish to make changes to the rating system are encouraged to become involved in that process. If the project team is limited by code requirements, scope of project or other restrictions from implementing strategies that will allow the project to achieve additional points under Water Efficiency Credit 1 for LEED 2009, than the project may be unable to pursue those additional credits. Given the varying scope of projects, not all credits may be achievable for all projects. Furthermore, it appears that the design team has not considered the alternative baseline for commercial faucets, that of 0.25 gallons per cycle. The consideration of this baseline allows for other technology avenues for water use reduction. It should be noted that the purpose of the Water Efficiency credits is to reduce the Volume of potable water consumed. Volume is dependent upon two variables, flow rate and time (V=RT). In addition to a focus on volume, several strategies that control the time factor are also available. Finally, dual-flush toilets are a behavioral solution representing only one technology path out of many that could yield savings over the baseline, all of which are non-behavioral and subject to independent timed controls. Applicable Internationally.
Related Addenda (Corrections & Interpretations)