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Water Saving Toilets

October 27, 2009

Water Saving Toilets

Water-saving toilets are now standard on all new construction because of a 1992 federal mandate for plumbing fixture manufacturers. Also known as low-flow toilets, water-saving toilets use 1.6 gallons per flush (gpf) of water or less, compared with older toilets that use 3.5, 5.0, and up to 7.0 gpf. The 1.6 gpf models significantly reduce the amount of fresh water consumed and the corresponding amount of blackwater generated. For example, using a 1.0 to 1.6 gpf toilet instead of 3.5 gpf models cuts indoor water use by more than 15%; when used instead of a 5.0 gpf toilet, it cuts water use by 20—25%.

Performance and Standards

The earliest models of water-saving toilets were introduced in the 1970s. Some have been notoriously poor performers, requiring multiple flushes to remove waste completely. Often, these early models were not engineered specifically to use less water, but were simply modifications to existing conventional toilet designs. By contrast, high performing low-flow toilets currently available are engineered to use less water and use it more powerfully. Today's high-performing models do remove waste as efficiently, or more efficiently, than conventional toilets while using much less water.

WaterSense has recently announced the first product specification that covers high-efficiency toilets (HETs)—those that use 1.28 gallons per flush (gpf) or less. WaterSense (www.epa.gov/watersense) is a voluntary public-private partnership program sponsored by the U.S. Environmental Protection Agency (EPA). With the announcement of the final HET specification, manufacturers, retailers, and distributors of water-efficient plumbing fixtures can use third-party certification to gain permission to use the WaterSense label on their products. In time, consumers will be able to recognize products with the WaterSense label as quality and high-performing water savers.


A variety of high-performing, low-flow toilets is available for residential use. Using different technologies, they provide a clean, efficient flush while meeting the 1.6 gpf maximum.

Source: HGTVpro.com