we have a bit of interesting situation in our project building: of the 181 installed water closets, 37 are Islamic toilets, which use a trigger spray rather than a flush mechanism.
we are trying to get our head around how to best account for this, since it is difficult to establish not only the amount of water used per use, but also the number of times that these toilets are actually used on a daily basis (the organisation who owns and uses the building has a diverse and multi-cultural staff contingent).
does anybody have any experience with this? any smart suggestions on how to account for this? or should we actually submit a CIR for this?
many thanks!
Petra Hajná
Sustainability ConsultantSkanska Czech Republic
189 thumbs up
June 6, 2011 - 9:23 am
I would ask some questions like these...
Who is manufacturer of those closets?
Do they have some product sheets?
Do you count FTEs or actual number of people in your project?
Do you follow any local LEED rating system?
Susan Walter
HDRLEEDuser Expert
1299 thumbs up
June 6, 2011 - 3:19 pm
The manufacturer should be able to give you a flow rate for the fixture. (Is it difficult due to variable length of the spray or the age of the fixtures if they are existing?) I would then build a different fixture group for these toilets. As for use rates, these shouldn't vary from the regular toilet use rates. That figure is based on human needs. Anyone using a fixture should be counted and there are a lot of conversations on how to account for various different populations in the other WE forums so I won't repeat that conversation. The foot baths I would treat like process water.
Jutta Berns
onwer and principalecocentric (pty) ltd.
130 thumbs up
June 6, 2011 - 4:14 pm
many thanks for the comments!
agree with the comment on use rate - this does make sense.
we do have the flow rates for the trigger spray, but finding it difficult to establish the length of the spray.
to be more specific and thinking out loud: the flow rate is 10l/minute (2.6gpm), all other WCs installed have flush rates of 3 - 6l/flush (0.8/1.6gpf). if we build a different fixture group for these toilets, we would, of course, need to include them under flow fixtures and could then possibly include them under the fixture family of a 'pre-rinse spray valve', in which case we could take a stab at average length of use?
Helen Samuel
Senior Tax AccountantErnst & Young
5 thumbs up
November 20, 2013 - 7:14 pm
I have the same situation, in which we are using trigger sprays in many of our water closets. The manufacturer provided the flow rate, so we have that information. I am stuck on the same question - what duration to use?? Did you end up going with "pre-rinse spray valve"? I think that "shower" better describes the purpose, but obviously it is not used for 300 sec.
Right now, we have it classifed as "Shower," with a duration of 15 sec.
What did you end up doing? And what did the reviewers say?
Melvina Pramadya Puspahati
Sustainable ConsultantBPM GmbH
November 3, 2023 - 4:57 am
I have a similar case, if the WCs installed have flush rates of 3 - 6l/flush (0.8/1.6gpf). what did you input in the calculator for the flush rate)? sould it be 3lpf or 6lps? thanks Jutta
Umesh Atre
Director of SustainabilityStudio8 Architects
8 thumbs up
November 16, 2023 - 11:09 am
Hi Melvina - If you have a dual flush WC, you should be able to enter both flush rates in the LEED v4 Indoor Water Use Reduction Calculator, and it will calculate a weighted average that you can use. Best of luck.