Blog Post

Exploding Low-Flow Toilets

In 1997, humorist Dave Barry wrote a newspaper piece titled "The Toilet Police," about those newly mandated 1.6-gallon low-flow toilets that honestly and truly deserved to be dumped on. The column is still floating around the internet, and clearly people are still moved by it. But, y'know, that was over a decade ago.

There are still crappy toilets to be had, just like there are lousy products of all sorts readily available, but smart toilet makers have strained to get the kinks out to the point that a one-gallon flush can outperform some of those old three-and-a-half-gallon water-hogs. It looks like Dave is still making a stink with that old log, judging from his website. But an exploding toilet under almost any circumstance is entertaining. A number of the most efficient commercial and residential toilets available are listed in GreenSpec; the state-of-the-industry and the standards considered by its research team are described as follows:

Since 1992, federal law has mandated that nearly all new toilets use no more than 1.6 gallons per flush (gpf) — the exception being commercial blow-out toilets, which are still allowed to use 3.5 gallons in some states. As toilet flushing is the largest single use of water in most residential and commercial buildings (accounting for up to 40% of residential use), water savings from toilet replacement is very significant.

In addition to improvements to the traditional gravity system, pressure- and vacuum-assisted flushing systems have been developed that offer superior performance, albeit with the addition of some noise. Dual-flush toilets have been available for years overseas and are now making inroads in the U.S. These save additional water by making two flushes available: one for solid wastes and a lower-volume flush for liquids and paper. Products listed here must meet the minimum standards of the Uniform North American Requirements (UNAR) for toilets, which includes elements of the Maximum Performance (MaP) flush-quality testing protocol and Los Angeles Supplementary Purchase Specification (SPS), which discourages the use of toilets that might be adjusted to use significantly more water. Products listed here use at least 20% less than the federal minimum of 1.6 gallons (6 liters) per flush — that is, 1.28 gallons (4.8 liters) or less. The toilet must also evacuate at least 350 grams of solid waste per flush, as tested under the Maximum Performance (MaP) protocol. Toilets that are included without MaP testing are extremely low-water use or have other unique green features. For dual-flush toilets, we factor water savings by averaging the high and low volume flush levels. Two reduced flushes and one full flush cannot average more than 1.28 gallons per flush. Other factors considered in GreenSpec evaluations include bowl washing effectiveness and water surface area.

Want more? Of course you do. See "All About Toilets," an archived feature story from Environmental Building News.

Published December 5, 2008

(2008, December 5). Exploding Low-Flow Toilets. Retrieved from https://www.buildinggreen.com/blog/exploding-low-flow-toilets

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