Innovative solutions for creating healthy, efficient, eco-friendly homes

Bathrooms for the 21st century

Hands-free faucets, water-saving toilets, improved ventilation, mold-resistant building materials, radiant-heated floors. Technology has come to the bathroom, marrying efficiency, conservation and comfort in a whole new way.

Once required only to be functional, the bathroom is evolving, becoming more of a spa-like setting, a place for relaxation and unwinding, says Diana Kostigen of Comtec, a North Carolina-based home electronics designer and installer. Today's bathroom also is more high-tech. Fans and radiant floor-heating systems can be programmed to turn on and off as needed, which means potential savings on your electrical bills.

Savvy homeowners also can save on their water and heating bills, thanks to innovative designs that have improved the efficiency of faucets, toilets, fans, flooring and building materials.

Water-saving fixtures

A typical family home uses an estimated 101 gallons of water per capita per day (gpcpd). Toilets account for almost 30 percent of indoor water use -- more than any other fixture or appliance. So it's not surprising that the Partnership for Advancing Technology in Housing (PATH), a public/private organization based in Washington, D.C., recommends water-efficient plumbing for both new and existing homes.

When it comes to water-saving features, however, there's a catch, says Shawn Martin of the National Association of Home Builders Research Center. Delivering less water through a fixture is easy, he notes. The key is to design faucets that deliver less water but still provide adequate cleaning performance, so the user's behavior won't change significantly.

In other words, there's no point in installing water-saving fixtures if users let the faucet run longer or flush the toilet several times because the fixtures aren't performing as expected.

These days, there's a growing list of bathroom fixtures available in water-saving models, including faucets, shower heads and toilets.

Faucets and showerheads — When it comes to saving water at the tap, aerators are the key, with the newest technology compensating for changes in inlet pressure to keep the flow consistent. Today's low-flow faucets have a flow rate of 1.5 to 2.5 gallons per minute, compared with standard faucets with 2.5- to 5-gpm flow rates. Low-flow shower heads use about 2.5 gpm, compared with between 4 and 5 gpm used by conventional heads, according to PATH.

But it isn't enough to reduce water flow; homeowners still want to feel clean, and that means delivering the water with enough force to counterbalance the reduced flow. Delta's H2Okinetic technology, featured in the Vesi custom shower system from Brizo, manages water-droplet size, velocity and coverage to deliver 1.6 gpm in a spray that feels like 2.5 gpm. This results in a 36 percent decrease in water use, according to the company.

Similarly, Kohler's MasterShower collection has a flow rate of 1.5 gpm, combined with a range of water intensity and coverage options to suit the user's preference.

Electronic faucets — Hands-free or touchless faucets are showing up in more and more homes, perhaps because they provide dual benefits: They reduce the transference of germs by eliminating the need to touch the handle to operate the faucet, and they conserve water, which flows only when a hand or item such as a toothbrush triggers a sensor in the faucet. Since running the tap wastes approximately 5 gallons of water per day, touchless faucets can really plug up the water leak.

Popular touchless models include Delta's eFlow faucet, billed as the industry's first residential hands-free faucet, and Aquaista's handcrafted ceramic and brass faucets, among others.

The Solis EAF-275 solar-powered hands-free faucet from Sloan Valve takes efficiency to a new level by combining the latest advances in solar power with cutting-edge electronics. It has an electronic sensor that automatically turns water on and off, and an integrated solar-energy module that converts light from any source into electricity to run the faucet.

Water-saving toilets — In 1995, the National Energy Policy Act mandated that all new toilets be water-saving models, using only 1.6 gallons of water per flush, compared with the old styles, which required 3.5 gpf. Low-flow toilet designs include those with large drain passages and redesigned bowls and tanks for easier wash-down, while others supplement the gravity system with water supply-line pressure, compressed air or a vacuum pump.

Replacing an old toilet with a water-saver model can save an estimated 7,900 to 21,700 gallons of water per year, according to the American Water Works Association, and reduce your water bill significantly.

Another option is a dual-flush system, such as the Aveo, Hommage and Editionals toilets from Villeroy & Boch, and the TwoFlush system offered by Aquanotion. These toilets have two levers, one for a small (half) flush for liquid waste and a second for a larger (full) flush for solid waste. They use 23 to 32 percent less water than conventional 1.6-gpf fixtures.


Effective ventilation is the best way to prevent mold from growing in the bathroom, says Dana Bres, a research engineer with PATH. When choosing a bathroom fan, he notes, homeowners should consider two aspects: the noise level of the fan when it's in use, and the area the fan needs to ventilate.

Many bathroom exhaust fans are so noisy that homeowners choose not to use them, Bres says. As a result, humidity in the bathroom may reach levels where mold growth occurs.

To determine how loud a fan will be, check the product literature for the sone level. The noise level a fan produces is expressed in sones; the smaller the number of sones, the quieter the fan, Bres explains. Some older fans produce four or more sones of noise, while newer, quiet fans produce as few as 0.3 sones. Another way to control fan noise is to select an in-line fan, where the fan and motor are placed in the attic some distance from the bathroom.

To choose a fan that's the right size for your bathroom, you'll have to perform a few quick calculations. You should aim for eight air changes per hour. First, determine the cubic feet of the room to be ventilated (width times length times height), and multiply that number by eight (the desired number of air changes per hour). Then divide that number by 60 (minutes per hour), and you'll arrive at an answer that represents the cubic feet of air you need to exhaust per minute (cfm). Check each fan's specifications, and purchase one that meets or exceeds that figure.

Look for a fan with a time-delay shut-off function, so you can run it long enough to vent the bathroom properly at least 20 minutes after showering or bathing, according to the Home Ventilating Institute, though some experts recommend running the fan as long as an hour to remove as much moisture as possible.

Today's ventilation fans are not only getting quieter but more energy efficient as well. Panasonic, for instance, has a Whisper Green model, which is up to 400 percent more energy efficient than minimum Energy Star requirements. Some Panasonic fans also include a number of functions that help improve efficiency, such as occupancy (motion) sensors and humidity sensors (dehumidistat). Often used in bathrooms to vent excessive moisture, these sensors turn the fan on when relative humidity reaches a certain level.

Mold-resistant materials

While combating moisture buildup with proper ventilation is essential, using moisture-resistant materials in the bath can provide additional protection at a nominal cost, says PATH's Bres.

Two building products from Georgia-Pacific are designed to be mold-resistant, making them ideal for the bathroom. DensShield tile backer board has glass-mat facings and an acrylic coating that blocks moisture from entering the wall cavity. An alternative to cement board and fiber-cement board, it's strong and easy to install, and it allowed no mold growth during a four-week controlled laboratory test.

Similarly, Paperless DensArmor interior wallboard is a mold-resistant interior gypsum panel designed for use on moisture-prone interior walls in bathrooms, as well as in kitchens and basements.

When building or remodeling a bathroom, consider putting a solid air barrier such as drywall or Thermo-ply on the inside surface of the wall where the tub or stand-up shower will be located. This will make the surface warmer and increase the room's overall comfort level. And don't overlook the floor, especially if it is over an unheated basement or crawlspace. Use spray insulation under the floor to increase energy efficiency.

Other mold-resistant building materials include MR-faced formaldehyde-free fiberglass insulation from Johns Manville, which has an EPA-registered mold inhibitor on the facer and laminate; USG's Sheetrock Humitek gypsum panels, which have a mold-resistant gypsum core encased in mold-resistant recycled face and back papers; and Perma-White mold-resistant paint from Zinsser.

Radiant floor-heating systems

If you hate the feel of cold floors on chilly mornings, then a radiant floor-heating system might be just what you need. Radiant floor heat comes in three types: hot water (hydronic), electric, and radiant air, where air is the heat-carrying medium. There are two kinds of installations: wet, which uses the large thermal mass of a concrete slab floor or lightweight concrete over a wooden subfloor; and dry, where the radiant tubing is sandwiched between two layers of plywood or attached under the finished floor or subfloor.

While most radiant systems use hot water in tubes under the floor (a hydronic system), smaller applications may be able to use an electric radiant system, Bres explains. For homes that don't have hot-water heating, the electric radiant systems provide design flexibility.

Electric radiant floor heating consists of a thin heating cable factory-mounted on a flat, sturdy mesh backing. The systems are low wattage, consuming 10 to 15 watts per square foot. As such, a system covering most of the floor of a bathroom would require 500 to 1,000 watts. Used with a timer, this could be a great option for the homeowner, warming the floor before the morning rush.

Operating a heated floor in a medium-sized bathroom will cost on average 5 to 10 cents a day for a two- to three-hour cycle, says Nicolas Mottet of Warmly Yours, an Illinois-based manufacturer of electric radiant floor-heating systems. A floor-heating system is typically controlled by a digital programmable thermostat that allows you to wake up to heated floors in the morning but turns itself off and saves energy and money when you're not using the room.

Floor coverings for radiant floor heating range from ceramic tile (the most common and effective choice, since it conducts heat well from the floor and adds thermal storage because of its high heat capacity) to vinyl, linoleum and wood flooring, as well as carpeting. Keep in mind, however, that any covering that provides insulation will reduce the effectiveness of the system.

Radiant heat panels

You can use radiant wall or ceiling panels to provide supplemental or zoned heat, or as the primary source of heating for an entire building. Since the panels warm the occupants, not the room, it's essential that their placement be determined carefully for optimal effect.

A radiant panel's quick response time (superior to any other heating technology) and its ability to be controlled individually for each room can result in cost and energy savings compared with other systems when rooms are occupied infrequently, according to the U.S. Department of Energy. In addition, PATH notes, electric radiant ceiling panels can significantly reduce energy consumption and installed capacity compared with an electric baseboard system.

Finally, Bres says, when considering electrical appliances in the bathroom, it is important to remember energy conservation. Look for the Energy Star label for fans and lights on the products you select.