"High-Performance" Green Fixtures

In fact, water efficiency is already gaining importance in standards of sustainability commonly utilized by architects, such as the U.S. Green Building Council (USGBC) LEED® Green Building Rating System. (Water-conservation credits offered in LEED are explored in depth later in this education module). One could build a project with a host of futuristic power-saving and carbon-reducing elements, like photovoltaic windows or a geothermal heat-source capture, and still sacrifice a higher LEED rating by ignoring water use considerations.

So what constitutes a "high-performance fixture?" HETs make the grade as high-performance fixtures. In the main, the UNAR standard of 1.28 gpf (1.68 gpf for models with a field adjustment to the tank trim) satisfy the criteria needed to earn a superior performance rating.

The USGBC has also set a standard for what it calls a "green toilet"-an important element of the LEED for New Construction (LEED-NC) rating-which should:

1. Flush well with 1.28 gpf or less.
2. Require minimal cleaning with environmentally unfriendly detergents.
3. Be user friendly and comfortable to all possible occupants and visitors-in other words, meet universal design criteria and flush quietly.
4. Be the major tool in reducing indoor potable water consumption.

Let's look at a couple of high-performance models, to see what features contribute to water conservation. For high-end residential applications, there are one-piece standard gravity fixtures with a 1.28 gpf flush and a 3-inch wide valve-more than twice as large as the conventional valves. A wide, glazed trapway will enhance its performance further. For commercial settings, 1.28 gpf flush is preferred over the EPAct baseline 1.6 gpf EPAct baseline, earning the fixture an HET designation. Pairing with a carefully matched flush valve is crucial, but the performance can be further enhanced by including an infrared sensor to operate the valve and a 2-inch-wide, fully glazed trapway.

In general, there are a few specifications that should also guide the choice of toilet fixture, some of which may relate only tangentially to the issue of conservation but are nonetheless important:

Finish. Finish, for instance, has been shown to contribute to performance in many studies. For the two examples above, the glaze on the porcelain or china used in the bowl and trapway was mentioned as a performance factor. Newer, smoother "nano-glazing" technologies are now available that appear smooth even under an atomic microscope, and feature an ionic barrier. The result is increased resistance to staining, bacteria and mold, as well as reduced maintenance needs. A damp cloth is sufficient to wipe the bowl sparkling clean. (Come to think of it, that will conserve water.)

Because obesity has become a national health concern, many building designers and owners are taking that into consideration by adding extra structural support for bathroom fixtures, such as wall-mounted toilets. Photo courtesy of Zurn Engineered Water Solutions

Flapper.Regarding durability, sensor technology can eliminate some concerns over the durability of the valves. Still, toilet flapper specifications are still critical. Chemical cleaners, tank additives and chlorine tablets entered the market place some time ago and began to cause many flappers to deteriorate faster than normal. The industry has made several attempts to create flapper standards which would be durable even under extreme exposure to chemicals, says John Koeller of the California Urban Water Conservation Council (CUWCC), based largely upon the earlier work of the Metropolitan Water District of Southern California and the Los Angeles Department of Water and Power for their procurement specifications.

Weight loading. Some testing has also been done to determine toilet bowl adequacy in handling higher weights. This is not a delicate topic, but most health authorities agree that our country faces an obesity crisis, if not an epidemic. Today's fixtures have to be equipped to handle higher loads, particularly in geographic regions with particularly high rates of obesity, and especially for wall-mounted models. Many of these tests are current or recently finished, and results should be available. Manufacturers should be able to direct a query to the proper test lab or published study.

High-Efficiency Urinals

Urinals represent an excellent opportunity to conserve water, because the technology has progressed significantly. Since the waste is liquid-only, engineers developing "green urinals" have been aggressive in reducing the water required for an adequately clean and sanitary fixture after use.

As there are HETs, so are there HEUs, or high-efficiency urinals. According to the EPA, HEUs operate at 0.5 gpf or less-an enormous improvement over traditional 1-gallon urinals. What's more, new urinals are not necessarily needed to achieve these results. Retrofitting valves can suffice in many cases, and offers an opportunity to consider replacing traditional valves with sensor-operated ones. (If cost is an issue, some valves can be retrofitted without being replaced.)

"High-efficiency urinals offer up to 87 percent savings over traditional 1-gallon urinals," says Sean Martin, with Zurn Commercial Brass and Fixtures Operations. "The life-cycle cost per unit is only about $30-$40 per year, depending on what part of the country. And they can elevate the level of hygiene if they have hands-free operation."

Also, new urinal technology continues to improve. Some models combine computer-modeled shapes with ultra low flushing (ULF), as low as a pint per flush--0.125 gpf. Flushless, waterless urinals have also been introduced, and while they may have drawbacks in operations, many building managers have field-tested the products with considerable success. The concessionaire at the Statue of Liberty since 1931, Evelyn Hill, recently installed waterless urinals in its men's room. The company believes, based on attendance at the national monument, that they may save as many as 385,000 gallons of water per year.

The challenges of waterless and ULF options, however, should be carefully considered. Flush-free urinals require cartridges to absorb liquid waste; the problem then is disposal of the cartridges-another sustainability quandary-as well as the cost of replacement cartridges. ULF valves may effectively clean the porcelain fixture, but may not use enough water to keep salts and minerals from collecting in the drainline. These deposits could ultimately lead to damaged plumbing.

A solution to both of these problems might be to create a fixture, perhaps run with a special sensor valve, that operates at the ULF specs but occasionally flushes more water than normal. This would keep the bowls and pipes clean, and could still save up to 87 percent over the old 1-gallon flush standard.