Existing Blow-out toilets

Russell Philstrom

LEEDuser Basic Member

7 thumbs up

June 19, 2015

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?

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Carlie Bullock-Jones

Principal

Ecoworks Studio

LEEDuser Expert

148 thumbs up

Wed, 12/30/2015 - 23:23

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.