The LEED NC for Retail rating system indicates a baseline performance of 1.6 gallons per flush (gpf) for all water closets except blow out fixtures, which are assigned a baseline performance of 3.5 gpf. As I understand it, blow out fixtures differ from tank-type water closets in that they are wall mounted and rely on water pressure rather than gravity for flushing. They are typically installed in public places at least partly because tampering with them is more difficult.
I am unclear whether "siphon-jet" water closets such as the model described below would be considered a blow out fixture or not for the purposes of this credit.
The Sloan WETS 2050.1201-1.28 SOLIS is sensor-activated flushometer and wall-hung fixture with siphon-jet flushing action and 1.28 gpf. Specs are available at the following URL:
http://www.sloanvalve.com/Specifications/WETS-2050-1201-1.28_Solis.pdf
Karen Blust
Green Building ConsultantThe Cadmus Group
124 thumbs up
February 25, 2011 - 5:45 pm
According to Kohler, a blow-out water closet is one that has a non-siphonic trapway at the rear of the bowl, and integral flushing rim and jet. Since the water closet you referenced has “siphon-jet flush action” I would assume that it is not considered a blow-out water closet and would use 1.6 gpf as its baseline flush rate.