Hello Everyone,
We receive a data sheet from a manufacturer of a shower head but we do not know how to know if the flow rate meets the prerequisite,LEED or not, because the manufacturer did not clearly write the flow rate but they provided a curve of flow rate according to pressure (He gave the flow rates that correspond to pressures between 1 bar and 3 bars), while LEED specifies the flow rates that correspond to the pressure of 415 KPA / 4.15 Bar. What can I do knowing that the manufacturer does not give any flow value for 4.15 Bar ?
Bipin Karki
Sustainability Project Manager87 thumbs up
December 4, 2020 - 8:50 am
Hello Sara,
There is v4 addenda 100001990 for this. You may want to check it.
Pressure testing standards
Supply water pressure and flow rate pressure testing standards vary throughout the world. For consistency, it is recommended that all projects use the flow rates reported by the manufacturer at 60 psi (415 kPa) for lavatories and kitchen sinks and 80 psi (550 kPa) for showerheads, or obtain the rated flow rates from an independent testing company.
If the manufacturer or testing company cannot provide the rated flow rate, project teams may use on-site tests to report the most accurate volume of water use. The fixture performance baseline would be developed by testing a baseline fixture onsite in the context of the building water pressure. The design case would use the actual measured flow rate of the fixtures installed in the project. The underlying assumptions used for calculating projected water use savings must remain consistent between the baseline and design cases."
If you want to use the on‐site test method, then per the addenda, you would also need to test a baseline fixture (meaning a showerhead
rated 1.75 gpm at 80 psi/6.62 lpm at 550 kPa) on‐site in the project to determine the baseline flow rate at the building’s water
pressure, and provide supplemental calculations as necessary with the adjusted measured showerhead baseline. Or install pressure
compensating aerators (PCAs) which deliver consistent flow rate regardless of pressure differences.
Or, You may simply use the following addenda ID#100002213 - v4 International tips: PCA
“Projects served by water supply pressures different than specified in LEED v4 may install pressure compensating aerators in flow fixtures to achieve the desired flow rate without compromising user satisfaction.”
Note that projects in countries without a WaterSense equivalent labeling program must meet the Table 6 flush and flow rates for fixtures which are WaterSense eligible. The maximum allowable flow rate for showerhead fixtures is 7.6 lpm (according to Table 6 of the Reference Guide)
Hope this helps!