Washington - The U.S. Environmental Protection Agency has announced the creation of a whole-house WaterSense specification that can be used by homebuilders and developers.
The intent of the Water-Efficient Single-Family New Home Specification is to reduce indoor and outdoor water usage in new homes and encourage community infrastructure savings, according to the agency. The specification will be applicable to newly constructed single-family homes and townhomes, three stories or less in size.
There are more than 120 million homes in the U.S., EPA noted, and about 1.5 million new homes are constructed each year. On average for all homes, 70% of household water is used indoors and 30% is used outdoors.
Based on 1998 numbers from the American Water Works Association Research Foundation, EPA pegs indoor water use at an average of 69.3-gal./day, with toilets consuming the most, 18.5-gpd, followed by clothes washers at 15.0-gpd and showers at 11.6-gpd. Leaks, according to the AWWA statistics, consume 9.5-gpd, or 13.7% of the total.
“The WaterSense Labeled New Homes program is an initiative designed to actively promote the transformation of the mainstream home building industry towards increased water efficiency,” EPA said.
Homebuilders would be required to train homeowners on their water-consuming fixtures and appliances and supply them with an operations and maintenance manual.
Because flow rate is a function of water pressure, the specification would establish a maximum service pressure of 60 psi. Compliance with the specification would require use of a pressure regulating valve downstream of the water meter.
Toilets would have to be WaterSense-labeled high efficiency toilets. The HETs have a maximum effective flush volume of 1.28-gal./flush and must effectively clear 350 grams of soy-based media.
All bathroom faucets installed in the home would be WaterSense-labeled bathroom faucets. The WaterSense specification sets the maximum flow rate of faucets and aerators at 1.5-gpm tested at a flowing pressure of 60 psi. The specification also includes a minimum flow rate of 0.8-gpm tested at a flowing pressure of 20 psi. Kitchen faucets would have to comply with the Federal limit of 2.2-gpm at 60 psi.
This specification does not establish a new maximum flow rate for individual showerheads, although the agency noted that it currently is in the midst of developing a new WaterSense specification for showerheads. Once that new specification is in place, it will supersede the 2.5-gpm allowed under current law.
The specification does, however, establish a total allowable flow rate from all showerheads flowing at any given time at 2.5-gpm per shower compartment. This requirement also applies to rain systems, waterfalls, bodysprays and jets. This specification defines a shower compartment as an area no larger than 2,500-sq.in. A half dozen showerheads and bodysprays putting out 10-gpm or more would not pass muster.
An exception to this requirement is the use of recirculating showers that would capture shower water in a reservoir and recirculate it to the sprays.
Showers must be equipped with valves that comply with ASSE 1016 for ASME A112.18/CSA B125.1 and designed to provide thermal shock and scald protection at the flow rate of the showerhead that is installed.
The draft specification, citing statistics from the Home Builders Association of Metro Denver, Guide to the 2007 Built Green Checklist, notes that American households waste an average of 10,000 gal./year waiting for hot water. The specification calls for some form of “structured plumbing” advocated by hot water guru Gary Klein, formerly with the California Energy Commission and now running his own consultancy, Affiliated International Management LLC.
All hot water pipes, both above and below ground, would be insulated to a minimum of R4 and each home would be equipped with a choice of demand-initiated hot water recirculating system, a whole house manifold system, and/or a core plumbing system. The systems are to be designed to contain less than 0.38-gal. of water between the hot water source and any hot water fixture for whole house manifold and core plumbing systems, and 0.13-gal. of water between the recirculating loop and any hot water fixture for demand-initiated water recirculating systems.
The draft specification also contains requirements for dishwashers and clothes washers (both must be Energy Star rated), and evaporative air conditioners, water softeners, drinking water filtration systems and whole-house humidifiers, with an eye toward reducing blow-down or regeneration water that goes down the drain.
Outdoors, the specification states that no more than 40% of the surface can be turf grass. The rules would also regulate irrigation systems and outright bans ornamental water features, such as fountains, ponds, waterfalls, man-made streams and other decorative water-related constructions, because “these water features serve no functional or practical purpose …”