Our project is in a 57-story building where the existing toilets are original to the building (1972) and are blow-out toilets at 3.5gpf. To replace the existing toilets and install a modern HET would require the wall to be opened up and the existing waste piping and carriers to be replaced and modified. This is a large expense to our project. We have located a 3-hole blow-out toilet at 1.6gpf that could be used to replace the existing toilet and get some pretty good savings. At the same time I have seen language in LEED's additional guidance docs that projects cannot get any savings from blow-out toilets. I feel that our project is meeting the intent of saving water but it just happens that our baseline/existing condition has toilets that unfortunately use a lot more water than current code. Any advice on how LEED would evaluate this?
You rely on LEEDuser. Can we rely on you?
LEEDuser is supported by our premium members, not by advertisers.
Go premium for
Carlie Bullock-Jones
PrincipalEcoworks Studio
LEEDuser Expert
220 thumbs up
December 30, 2015 - 6:23 pm
Hi Russell,
Per the USGBC Water Use Additional Guidance document there appear to be two options for calculations due to existing piping limitations:
1) If the existing fixture is not replaced or the replacement fixture is higher than 1.6 gpf, the project may select the Blow-out Fixture option. In this case, the 3.5 gpf must be used in both the baseline and proposed case.
2) If the replacement fixture is a 1.6 gpf (or less), then the project may use the 1.6 gpf as the baseline and the proposed will be the actual fixture gpf.