Residential Water Use by Toilets

Toilets typically are the largest source of water use in the home, accounting for 30 percent of indoor residential water consumption.   Toilets are also major sources of wasted water due to leaks and/or inefficiency.  Fortunately, the water efficiency of toilets has been increasing and recent advancements have allowed toilets to use 20 percent less water than the current federal standard of 1.6 gallons per flush, while still providing equal or superior performance.

Three basic types of low-volume toilets are commonly available in the market today.  More information on the types of toilets can be found here.

Performance Testing of Popular Models

Everyone wants a toilet that “does the job” in one flush.  The Environmental Protection Agency (EPA) WaterSense Programand the non-profit organization Alliance for Water Efficiency both have compiled lists rating the performance of popular toilet models on the market today.

EPA WaterSense

WaterSense is a partnership sponsored by the US EPA and the primary goal of the partnership is to make it easier for consumers to find and select water-efficient products with the WaterSense label.  The label certifies products as water efficient based on independent testing and fixture specifications.  WaterSense labeled products are 20% more water efficient that their leff efficient counterparts and generally perform as well or better.  EPA WaterSense has produced a list of labeled HETs on the market today availabe to the public.

Alliance for Water Efficiency

The Alliance for Water Efficiency is a non-profit organization dedicated to the efficient and sustainable use of water.  The Alliance began in 2003 compiling a list of tested popular toilet models.  The list is now in its 15th edition and provides maximum performance testing (MaP) on over 1,200 different toilet fixture models.  Many of these models are WaterSense-certified HETs.  The list of can be found here.