All toilets and most showerheads today meet the federal water-efficiency standards, but not all of these products perform satisfactorily. With toilets and showerheads, we include products that meet or exceed WaterSense standards, which includes performance requirements—although we go beyond WaterSense where there are issues not adequately addressed by the program. We also look for other products that conserve potable water, such as rainwater catchment and graywater recovery and reuse systems.
While resilience—the ability to weather natural disasters and maintain livable conditions in the aftermath of disruptive events—is mostly an issue of building design and community preparedness, certain products can help. For example, almost all heating systems require electricity to operate even if their primary fuel is oil, gas, or wood pellets; systems that allow operation even if grid electricity is not available are more resilient in the event of power outages. Rainwater harvesting, water storage, composting toilets, and waterless urinals contribute to resilience not only in drought-prone areas but also during power outages in any home dependent on well water. Solar water heating systems that can operate without utility power, and back-up power systems that are more energy-efficient than standard generators, may have this attribute.
The Caroma H2Zero Waterless Urinal is a vitreous china, wall-mounted urinal that uses a one-way, air-tight, silicone mechanical seal that opens only during usage. A secondary, liquid (urine) trap is provided downstream of the mechanical seal to comply with U.S. plumbing codes. (Whether or not it actually complies with codes is subject to some debate—check with your code authority.) The absence of a plant-oil fluid seal (used in most waterless urinals) reduces operating costs, lowers burden on sewage treatment plants, and allows this urinal to be flushed periodically with a bucket of water to remove salt build-up on the pipes. The seal, along with a proprietary deodorizing block, should be replaced every 10,000 uses, according to Caroma. The H2Zero urinal comes in white and has a two-year warranty.
Read more on this product in "BuildingGreen's Product of the Week"
Compared with the federal-standard 1.0 gallon per flush, a single non-water-using urinal can save over 10,000 gallons of water per year (depending on the number of males in the building); when older 3 gpf urinals are replaced, the savings can be as great as 50,000 gallons per year.
GreenSpec lists high-efficiency urinals that use 0.25 gallons per flush or less, next-generation non-water-using urinals that use a lighter-than-urine fluid to provide the "trap" that keeps odors out of the restroom, and low-water-use flush valves.
Some manufacturers are offering waterless urinals using an elastomeric membrane to seal the drain, in some cases with and in some cases without a trap. (When combined with a trap, the trap is filled with urine, acting as a seal against sewer gases.) Due to questionable code compliance—these seals are seen as a prohibited mechanical trap—GreenSpec does not recommend use of elastomeric membranes alone, and does not list products relying on this. Products using such a membrane along with a trap may fare better, but GreenSpec advises caution.
WEc1: Water Use Reduction
WEc2: Innovative Wastewater Technologies
WEc3: Water Use Reduction
WEc3.1-3.2: Water Use Reduction
WEp1: Water Use Reduction—20% Reduction
WEp1: Minimum Indoor Plumbing Fixture and Fitting Efficiency
WEp1: Water Use Reduction
Ratings and Commentary