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Full-flushers prompt changes to green building standard

ASHRAE is proposing changing its 189.1-2011 green building standard to restrict the use of reclaimed municipal wastewater. It is also proposing limiting  full-flush toilets to 1.28 gallons per flush.


ASHRAE is proposing changing its 189.1-2011 green building standard to restrict the use of reclaimed municipal wastewater. It is also proposing limiting  full-flush toilets to 1.28 gallons per flush.

The 189.1 committee made the decision based on research that showed dual flush type toilets in commercial buildings are not effectively reducing water use because occupants nearly always use the full flush option. Therefore the committee is proposing reducing the full-flush capacity in the standard.

They are also proposing changing the use of reclaimed municipal water based on the fact that reclaimed water is highly treated, and so is a precious resource.

“It is unreasonable to allow the unfettered use of reclaimed water, considered a precious resource, as a means to save energy when there are more viable alternatives,” said Thomas Pape, a member of the committee.

The proposals restrict the use of treated reclaimed municipal water from being used for roof cooling and for watering green roofs or ground irrigation.  The only exception is during a period when the vegetation is being established. 

The committee noted that there are several other good options for watering green roofs, etc. such as grey water, condensate discharge, rainwater and cooling tower discharge.

The proposed changes to ASHRAE (the American Society for Heating, Cooling and Refrigerating Engineers) Standard 189.1 (Standard for the Design of HIgh-Performance, Green Buildings Except Low-Rise Residential Buildings) are part of addendum v, which is open to public review until January 14, 2013.  Click here.