ADA Compliance

To protect against sight-impaired individuals bumping into objects that are protruding out into hallways, corridors, or passageways, the Americans with Disabilities Act (ADA) requires that the protrusion be no more than 4 inches or 100 millimeters from the wall and into the space. Displays with leading edges that are within cane sweep, 27 inches high maximum, or a minimum of 80 inches above the finished floor are permitted to protrude any amount.

While some LED cabinets are thin enough to enable the structure to stay within 4 inches (100 millimeters), in many cases, the LED cabinets are 70 millimeters to 90 millimeters thick, so by the time the mount is attached, the display protrudes more than 4 inches (100 millimeters) from the wall.

One way to design around the protrusion is to build the display all the way down to the floor by filling in the space below the display. Then it is no longer a projection from the wall, but rather it is the wall, and ADA compliance has been achieved.

Another strategy is installing a guardrail at the floor around the display. With a guardrail, a cane will effectively keep a visually impaired individual from bumping into the display.

Architects can also consider embedding the structure into the wall to take up some of the depth. In other words, create a cavity or recess inside the wall.

While ADA compliance in these types of locations is feasible, it is important that the project team first evaluate whether installing an LED display in these corridor locations is really necessary in the first place. Further, it is questionable that the technology is actually suitable for the environment, as LEDs are very fragile and easily damaged by individuals touching the display, unless the LEDs are encapsulated. Additionally, the viewing characteristics are not optimal for up-close viewing. Consequently, there must be a strong need to justify installing a display in these hallway locations.

Photo courtesy of Draper Inc.

Curved LED video walls can be concave or convex—or, as in this example, they can be both for enhanced visual flow.

Cooling and Cable Management

Temperature control is an important aspect of LED video wall design, as maintaining a relatively constant, steady temperature will increase the useful life and reliability of the LED modules.

To keep the temperature from exceeding manufacturer recommendations, many LED displays are passively cooled, relying upon most of the heat to emanate through the front of the display, while the power supply units typically dissipate heat from the backside. A well-designed structure and surrounding trim package, along with vent holes at the top and bottom, will optimize convective cooling.

In some cases, HVAC or air-to-air heat exchangers will need to be used to dissipate the heat, though in some instances, flow-through fan cooling or the above-mentioned ventilation slots in the trim are sufficient.

In most projects, the architect works with the HVAC team to ensure that the BTU offset from the display is calculated into the HVAC load.

Another design issue is cable management. Traditionally, LED displays utilized a daisy chain of power and data cables from one cabinet to the next, and having adequate room for those cables was an important design consideration. Nowadays, more and more displays utilize internal power and data connections, which are typically inserted into the back side or at the top cabinet on each column. Some manufacturers then provide trim that matches the plug that goes on top of the LED cabinet.

The number of power cables that go to the display depends upon the size of the display and the number of LED cabinets multiplied by the power draw of each cabinet. The number of data cables is determined by the resolution of the display and the bitrate of the content being sent to the display. For example, a very high resolution display will require more cables, as there is more data going from the controller to the display. For higher bitrate content, it will require even more cables because there is more data being sent for every single pixel.

In project planning, some things to consider are how many cables will be needed and how the cables will be routed. If cable-less connectivity is an option, then this becomes less of an issue.

Architects also need to consider how the display will be controlled and where the controller will be located. The maximum distance between the controller and the display is based on cable length. Another consideration is the number of video walls that will be controlled (i.e., a single video wall or several video walls that will be networked).

Conclusion

Now that LED display technology sales have eclipsed LCDs, it is critical that architects to proactively address the integration of LED systems into their designs if LED is their display technology of choice for the project. This will ultimately protect the integrity of their building designs and enable the design and installation process to proceed in a seamless manner.

Further, by selecting high-quality mounting systems with a high level of adjustability and precision, this will produce the highest-quality, seamless LED display.

Barbara Horwitz-Bennett is a veteran architectural journalist who has written hundreds of CEUs and articles for various AEC publications. www.bhbennett.com