Architectural Record BE - Building Enclosure

International Restroom Design

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Sponsored by Sloan

Qualities of Plumbing Products for the International Market


In a true flushometer installation, water flows under pressure from the supply piping directly to the fixture. The required flow rate, measured in liters per minute (Lpm), is established by the hydraulics of the fixture. If the supply pipes are properly sized, an adequate volume of water will pass through the flushometer and permit the fixture to operate efficiently.

Photo of a flushomenter toilet.

A true flushometer is specifically built to address the needs in global commercial restrooms.

It is the use of the pressurized water supply that gives a flushometer a performance advantage over a tank toilet in commercial applications. In a tank toilet, the water used for the flush is first accumulated in the tank. The water flows by gravity into the fixture when the tank toilet is flushed. The energy behind the flush is created by the weight of the water in the tank. Because flushometers rely on the pressure and flow from the supply piping, there is more energy behind the flush, which is important in a commercial application and vital to using water efficiently and effectively. Flushometers also reset faster than gravity toilets (there is no refill time), which is another important requirement in a commercial installation.

Concealed tank toilets are commonly used around the world in the commercial restroom environment, and they are better suited for residential applications. Since tanks take time to fill up, they are not efficient enough for high-traffic restrooms typically required in commercial applications. Concealed tanks are also more difficult to install and maintain than most flushometers. In addition, flushometers are also easier to service than their tanked counterparts, making their maintenance easier and more cost effective. Finally, tanks have a reputation of leaking over time and thus wasting water.

Many global restrooms also use simple hold-open flush or metering valves (i.e., valves that don’t automatically shut off) for their plumbing solutions. However, a hold-open valve is ultimately inefficient, inaccurate, and unsafe. Typical problems arise particularly in the case of intermittent supply, which is common in many countries. Sudden changes in pressure can damage valves to levels of non-functionality. Floods are also a serious problem with hold-open technology. Because a hold-open valve will dispense water as long as the button is engaged, a flood in the restroom can occur if the button is stuck in the open position.

Many of the issues of hold-open technology can be solved with true flushometer technology. A flushometer will dispense the same amount of water every time, increasing water efficiency in a commercial restroom environment and delivering reliable and accurate performance with each flush. And compared to a hold-open valve that will dispense water as long the button is engaged, up to 75 Lpm/20 gpm, a flushometer will provide a limited flow of water, no matter how long the button is pushed.

One company in particular has manufactured a true flushometer specifically built to address these needs in global commercial restrooms. The design and engineering of this specialized flushometer goes above and beyond the typical true flushometer and provides the highest water efficiency and savings in global applications.

There are two different water delivery orientations: exposed and concealed. Exposed, as its name suggests, delivers the water in full view to the user via a pipe/flushometer or a visible tank. Exposed orientations are usually less expensive and easier to work on and maintain.

For concealed, the water is delivered from behind a wall directly into the fixture with only a flush activation button, sensor or handle exposed. This system, combined with gravity-fed tanks, is very popular in many international countries outside of the United States. The concealed flushometer is gaining popularity primarily for its accuracy and water conservation as well as its clean, modern look and less product surface area to maintain.


When it comes to fixtures, water closets come in three primary configurations: wall hung/wall mounted with wall outlet, floor mounted with floor outlet, and floor mounted with rear outlet. With wall hung, the bowl is mounted in a cantilevered fashion that protrudes from the wall horizontally and is supported by what is known as a carrier that is mounted securely to the floor. The carrier has an integral waste drain for the waste to pass through it to the main drain lines. The most popular design internationally is the wall hung.

The toilet bowls themselves come in two different rim shapes, elongated or round. Elongated is an oblong oval shape when viewed from the top. It is larger overall and can accommodate a wider variety of users. This shape is used almost exclusively in commercial (public/non-residential) restrooms and primarily in the United States. Round is more compact and takes up less room. It is the primary style in residential and hospitality settings for the guest rooms as well as small business environments with lower traffic/use.

Washdown is the overall predominant flushing method throughout the world, but is rarely used in the United States where siphonjet method is utilized. Washdown is powered by gravity with a tank that is either exposed or behind the wall. This method relies on feeding all of the water through the rim and basically “pushes” the waste out of the bowl via a short, simple P-trap. On the other end of the spectrum, siphonjet can be powered by a flushometer, pressure assist, or gravity and is the overwhelming style used in United States. This particular method relies on water that is fed through both the rim as well as a main jet located in the “well” at the bottom of the bowl. Siphonjet has a longer S-shaped trapway. When the flow of the water reaches a certain point, it initiates a siphon effect and pulls the waste out through the outlet. In the case of siphonjet or pressure assist, the waste is also forced out prior to the siphon effect.

When selecting and installing any fixture, it is important to specify a water delivery method that matches the pressure and water volume requirements. The water delivery system chosen differs on aesthetic and water efficiency. In a flushometer installation, water flows under pressure from the supply piping directly to the fixture. The required flow rate, measured in liters per minute (Lpm), is established primarlily by the hydraulics of the fixture rather than the valve. If the supply pipes are properly sized, an adequate volume of water will pass through the flushometer and permit the fixture to operate efficiently.


Selecting a faucet for commercial applications is no simple task. It’s much more than just finding a way to get water into a basin. The faucet represents a critical point of interaction—the culmination of a positive, hygienic experience that begins with a designer or architect’s vision. From an engineer’s perspective, it’s all about reliability, ease of installation and maintenance. Finding the right solution involves striking a balance among many (often competing) factors.

In restrooms with manual faucets, handles are a prime breeding ground for germs. Touching faucet handles after washing simply re-contaminates hands and reverses much of the good that came from washing in the first place. Therefore, touchless, sensor-operated faucets can contribute to a higher level of handwashing hygiene.

According to James Piper, P.E., in “Five Ways to Reduce Restroom Operating Costs,” (FacilitiesNet Magazine, July 2012), “Electronic faucets are a very effective means of reducing water use. In a typical installation, they can produce water savings in the range of 50 to 80 percent when compared to manual faucets. While the units are more expensive to purchase than manual faucets, the cost savings produced by using less water typically recover this additional first cost in one to three years.”

There are two different kinds of sensing technologies available: Active Infrared (IR) and Capacitance (C). Active Infrared sensing operates when a user’s hands reflect an invisible light beam, alerting the faucet to begin the flow of water. Infrared models are designed to provide easy, above-deck access to key components, and offer additional user enhancements. Capacitance sensing utilizes the human body’s own natural conductivity. When the faucet senses a hand, it starts the flow of water. There is no sensor window, and critical components are protected in a watertight, below-deck box. In some instances, the proper functioning of Capacitance technology can be inhibited by metal fixtures or the proximity of large metal objects.

Some electronic sensor-operated faucets use as little as one-third gallon of water per minute, a conservative flow that saves water while aptly supporting proper handwashing hygiene. These faucets are either hardwired or powered by battery, solar, or turbine energy. Solar faucets resourcefully derive power from any natural or artificial light source, faucets with turbines harness the energy of moving water.

Sensor faucets are preset to shut off after a certain amount of time, they save a significant amount of water, and accidental flooding can’t occur if a user leaves it running. And, because they are hands-free, they help reduce the spread of germs and keep the vanity area clean.


Sinks are the most visible of the functional elements in a commercial restroom. Floors, walls and mirrors may set the tone, but sinks pull together the designer or architect’s vision. Yet simply catching the eye isn’t enough. Building managers and engineers have higher expectations than ever.

As noted earlier, regulatory requirements and preferences differ by country. Choosing a sink that is IAPMO-certified is a good option since it has passed a complete battery of tests to prove it can stand up to any commercial application domestically as well as internationally. In addition, following ADA-compliance standards is important in many countries. In order to adhere to ADA domestic standards, one requirement is that a sink must be a maximum of 34 inches above the finished floor, which requires proper installation.

Choosing a sink that has detailed installation instructions, in the language spoken in that specific country, is also essential for proper installation. If a sink does not have installation instructions in the language of the country, choosing simpler installation options, such as angle brackets versus an enclosure, can reduce the risk of improper installation.

The sink also combines components such as faucets, soap dispensers, and on-deck hand dryers that also have to be evaluated. As previously noted, the electrical requirements vary per country, so the products chosen must be compatible or have a plug-in adapter if they are hardwired. An alternative option is to use battery-powered products. It is also important to ensure that repair parts and refills for soap dispensers. are locally available at a reasonable price.

Additional Factors to Consider

Price Points

Price is a factor as well, but usually only if the design isn’t groundbreaking. Price matters for varying reasons. For instance, in Latin America (in general) manual products are usually chosen over automatic, with cost the deciding factor: manual products are less expensive—at least on a first-cost basis—especially in developing areas.

Plumbing Knowledge and Licensing

Plumbing knowledge and licensing differs in many parts of the world, resulting in varying repair times and affecting ease of installation. It is extremely important to remember that not all plumbers are properly certified or certified at all in the same way they are in the United States, and manufacturers are not always locally based. This is especially true within South America.

Communication and Research

Above all, architects, designers, and engineers must communicate with their clients and do their research. It should be noted that a “global manufacturer” can do the regulatory research for the region a an architect is designing for.


1Health Aspects of Plumbing. Geneva: World Health Organization, World Health Organization, World Plumbing Council, Accessed 27 Sept. 2017. Published jointly by the World Plumbing Council

Resources (World Green Building Council) (Vanke Center Case Study) (Compensar HQ Case Study) (Whitepapers) (National Water Commission – Mexico) (China Compulsory Certification) (The National Bureau of Asian Research) (BREEAM) (Bureau of Indian Standards)

Graham Architectural Products logo.

Sloan is the world’s leading manufacturer of commercial plumbing systems and has been since 1906. The company is at the forefront of the green building movement and provides smart sustainable restroom solutions by manufacturing water-efficient products such as flushometers, sensor faucets, sinks, soap dispensers, and vitreous china fixtures for commercial markets worldwide.


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Originally published in Architectural Record