Water Efficiency

An in-wall toilet system offers special water efficiency benefits in a multifamily building. According to the U.S. Environmental Protection Agency (EPA), the highest percentage of water use comes from the domestic restroom. This makes the design of flushable toilets particularly important. In this case, it is the design of the flow mechanism and the controls that actuate it which are critical.

Traditionally, floor-mounted toilets with a manual flush have been the norm in many multifamily settings. However, toilets with dual-flush controls are becoming more common, since they allow the user to determine how much water is used for each flush appropriate to the need. Commonly, there are two choices for a standard and reduced water flow per flush, instead of being limited to only one standard choice. With such dual-flush technology built in, a household can reduce their water usage by thousands of gallons of water per year. In-wall toilet systems typically include such dual-flush technology activated by touch (or touchless) panels flush-mounted on the wall above the toilet. This provides a clear, elegant solution for the flush controls that help produce the dramatic water savings.

In-Wall Design

While some may think that a high-performance toilet needs to look clinical or austere, the reality is that there are contemporary design alternatives. That means architects do not have to lose their design concepts to achieve critical performance features. Rather, there are innovative products for bathrooms that meet the demand for sanitation, safety, and sustainability while also providing a high level of design. In order to accommodate a range of different project types, there are multiple fixture options to bring a design vision to life. Beyond these aesthetic benefits, there are also clear space savings achieved by recessing the toilet tank system into the wall, allowing for more usable space in restrooms in many cases.

In-Wall Performance

In addition to better water control that is available from dual-flush actuators, in-wall systems are a reliable and high-quality solution for designing contemporary bathrooms that meet the demands of all involved. Overall sanitation and safety are achieved by having less of the toilet system exposed and the bowl raised up from the floor. This adds to the comfort and convenience for users as well as ease of cleaning. In terms of maintenance, all working parts remain easily accessible, although the high reliability of this type of unit reduces the need for maintenance crews to access it in the first place. Commonly, the support frame is based on solid steel construction with a seamless, one-piece tank made of durable, leak-free, high-density polyethylene. Units are commonly tested and proven to support up to 880 lbs. (400 kg) without deforming the frame or the wall.

CONCLUSION

Creating well-designed multifamily housing is a multifaceted task. Fenestration is required in all buildings to provide views and daylights but still achieve targeted thermal performance. Interiors need to be attractive and durable, including the interior of elevators. Innovative materials can be used to enhance the building exterior and interior. Bathroom designs need to be easy to clean and space efficient. Large buildings require expansion joints to protect against inevitable movement. The strategies discussed in this course can help architects and designers address these multiple design criteria to meet the needs of the building owner, the occupants, and the environment.

BATHROOM RENOVATION CASE STUDY

Photos courtesy of Geberit

Project: Woolworth Building
Location: New York City, New York

The Project: The iconic, Neo-Gothic Woolworth building in New York was the tallest building in the world in 1913. It was owned by F.W. Woolworth, one of the original pioneers of the five-and-dime store. Originally designed by Cass Gilbert, the Woolworth building rises 60 stories over the southern tip of Manhattan. The top 30 stories, known as The Woolworth Tower Residences, have recently been converted into 33 one-of-a-kind condominiums that include in-wall toilet systems.

The Challenge: When it came time to renovate, the building’s owners, designers, and architects selected premium polished Italian marble for the interior walls and countertops; custom Italian millwork for the vanities; and top-of-the-line plumbing fixtures and fittings throughout. Joanna Stephens, Project Manager, CNY Group needed to meet the requirements for a luxurious interior that also extended to the numerous bathrooms and powder rooms. Extensive structural reinforcement as well as MEP (mechanical, electrical, plumbing) replacement was essential, and the challenge was to do so without disturbing the existing lower-level tenants or jeopardizing the building’s landmark status. The Woolworth Building has been a National Historic Landmark since 1996 and a New York City Landmark since 1983.

The Solution: “We installed in-wall toilet systems in all of the building’s 100 bathrooms, saving an average of nine inches of space per bathroom. Nine inches doesn’t seem like much until one considers that the cost per average square foot in the building can exceed $3300,” Stephens says. “The system combines the luxury the owners wanted with the practicality that renovators, maintenance professionals, and homeowners demand.” The in-wall system opens up more space in the bathroom by enclosing the unsightly toilet tank and other plumbing hardware inside the building’s walls. The sound-insulated tank helps deaden the flushing noise, which can reach 75 dBA on a standard toilet, especially important in luxury apartment buildings.

The combination of a dual-flush plate and advanced flush valve will save thousands of gallons of water every year. Residents will also benefit from the system’s dependability, improved accessibility, and extreme durability.

The Testing: Nothing about the renovation was left to chance. Prior to installation, CNY Group produced a full-scale mockup of a bathroom with the in-wall system to verify the strength of the system. The selected carrier for the wall-hung toilets supports up to 880 pounds exceeding American Society of Mechanical Engineers (ASME) A112.62 strength requirements. During a standard ASME test, a 500-pound (225 kg) weight is put on the edge of the fixture for five minutes and then tested to deflect not greater than 0.250 inches (6.3 mm). The standard establishes minimum performance requirements for framing-affixed supports for off-floor water closets with concealed tanks. The system is designed to be practically maintenance free. Should maintenance ever become necessary, the system offers easy and quick tool-free access to all internal components, including the fill and flush valves, through the decorative actuator flush panel.

The Results: The in-wall tank and carrier system allowed sleek design to be carried throughout the building without interrupting the full-height vertical marble wall panels. With a little help from the manufacturer, the designers achieved their vision, giving the historic building a contemporary feel.

Peter J. Arsenault, FAIA, NCARB, LEED AP is a nationally known architect and a prolific author advancing positive acoustical experiences through better building design. www.pjaarch.com, www.linkedin.com/in/pjaarch