Published in May 2004

IT/AV/MW/EC/GC Convergence: Users, Furniture, Infrastructure
By Joseph Bocchiaro III, CTS-D

It’s not all in the hardware and wiring.

      Among the more challenging aspects of IT/AV systems design is the incorporation of device connectivity into furniture and architectural millwork, and the connection of this furniture to building wiring. The growing need to connect notebook computers and network appliances in different situations has led manufacturers to develop hardware components specifically for this purpose. Although welcome additions to the AV designer’s repertoire, they create a new class of challenges for construction coordination, between IT (Information Technology), AV (audiovisual), MW (Millwork), EC (Electrical Contractor) and GC (General Contractor).
    Prior to their development, connectors for computers, document cameras, control panels and other AV devices were incorporated into custom housings and pockets. IT component manufacturers, already producing floor and wall connection solutions, began focusing on furniture housings. The large marketplace for such devices precluded any types of connectors other than power and voice/data (information outlet) jacks. Adding AV connectors to these specialized interfaces has been particularly problematic. This is where the IT/AV “rubber” meets the MW/EC/GC “road.”

‘Smart’ Furniture
     During the last 10 years, commercial furniture manufacturers have learned that they need to accommodate technology in a variety of environments. It began in corporate offices, where workstations required cabling for telephones, monitors and personal computers. The need was particularly acute in the corporate conference setting, where large tables require frequent connection of computer, telephony, and AV equipment. Furniture manufacturers began to produce desks and tables known as “smart” furniture, although there are not actually any active or “smart” components involved.
     Some furniture manufacturers have recognized the need for customization of the “smart” connections, and allow for the integration of various IT and power connectors, as well as customizable AV spaces. Some have developed their own systems, while others have incorporated commercially available devices. Some of those fit within larger families of components that may include connections to partition walls or raised floor systems.
Architects and interior designers have been eager to adopt “smart” furniture solutions, although often without understanding the special considerations that must be given to them. In their defense, however, it is largely the architectural community that has demanded attention to cable management and aesthetically pleasing technology components.
     The design team has many options besides available stock furniture equipped with connectivity devices. Numerous manufacturers of stand-alone components (standard or custom-made) are ready to install into furniture. Use of these components can transform ordinary furniture into “smart” furniture! Furniture specifiers should be aware of issues when selecting furniture to be electronically equipped. In particular, if furniture is to be stacked, folded or stored, the configuration of the infrastructure and cabling must be planned carefully.

Table Connectivity
     Furniture IT/AV infrastructure components come in many shapes and sizes. The least expensive are flush-mount plates with exposed connectors. Table pocket components embed these plates into the furniture, with one or two “pocket,” “bomb bay” or other doors for access. Brushes, “mouse holes” or indentations in the covers prevent cable abrasion and pinching.
More complex devices include boxes that manually or electrically “pop” up from the table, boxes that “flip” up on one hinged side and boxes that rotate, with a finished surface opposite the connectorized side. Whatever the form factor, these devices present the user with a surface area housing connectors, and a means of routing cabling to cable management beneath the work surface. 
     The most important consideration in table connectivity components is whether they provide a means for integrators to customize them, or must be configured and assembled at the factory. Also important: Is the device modular enough so installers can work on their own distinct area without disturbing other trades’ work?
     Another distinction is whether connectors and related mounting hardware are standard, readily available or project-specific, or whether they are unique to the device manufacturer. Modularity and physical separation within each category—electrical, IT, telephony and AV—are also desirable. These points are critical to the sequencing of trades’ work on the project site; devices must be installed and ready for a variety of sub-installation procedures.

Cable Management
     Secondary to the devices themselves, but equally important, is management of the cabling from the device to the floor, wall or to another furniture component. Some manufacturers equip their furniture interface products with standard or simple connection points, such that each trade can install cabling as necessary for the project. Others supply the products with fixed or custom-length cables, often with connectorized ends.
     This distinction is important because the cables’ termination points may vary from room to room, or may change during the course of the project. Some cables may have to be pulled in their entirety from an equipment cabinet or patch panel, for example, and terminated in a fixed-furniture situation at the furniture interface.
     Other cables may require connectors for presentation to a floor or wallbox. Still others may require frequent connection and disconnection to floor or wallboxes in different locations, necessitating flexibility in the direction and length of the cabling.
Regardless, cables must be managed beneath and within the furniture the device is affixed to. They must be secure and free from excess slack that users can accidentally pull with shoes, knees or hands. Complete design includes cabling raceways built into the furniture itself, particularly in table legs, that can hide cable bundles all the way to the floor- or wallbox connection point. Easy access to the entire cabling path is important for maintenance and capabilities upgrades.
     In locations that are not seen by participants, such as the underside of large conference tables, this often is best handled with hooks or standard cable raceway products. Holes in wood between millwork architectural components should be finished with grommets or other escutcheons designed to prevent cable abrasion. Pathways and raceways should be separated with respect to signal type, to match the configuration of the furniture interface.
     Work surfaces often contain excess cable, power supplies, transient suppressors, signal converters and other sloppy elements. The use of grommets, slots with brushes and other hardware can allow users to set up and organize the surface easily. This can make a great difference in extended meetings where numerous laptop computers, audio conference equipment, coffee pots, paperwork and other objects share the table. Often a combination of furniture interfaces, grommets or on-table raceways is desirable to both connect and hide cabling.

WELL-EQUIPPED TABLE BOX INFRASTRUCTURE DEVICE.

Room Connectivity
     A related critical and difficult coordination task for IT/AV/EC/GC professionals is the location of wallboxes and floorboxes. Often these infrastructure devices are positioned in a space prior to the detailed design of furniture locations. Changes in furniture layouts at a later date can be disastrous in cases where complete misalignments occur, such as when AV credenzas or desks are located on a different wall in a room!
     Furniture with intelligently designed cable pathways can be located perfectly above a floorbox or at a wall location such that no cables are seen whatsoever, or misaligned in such a way that cables become unsightly tripping hazards. This can be accomplished only when design- and construction-team coordination is managed tightly.
     Rooms with reconfigurable furniture locations are particularly problematic. Common practice involves aligning floorbox locations beneath as many anticipated furniture layouts as possible. This is accomplished by layering the furniture plans and looking for intersections. Furniture that allows for internal rerouting of cabling can accommodate floor or wallboxes near different table legs or pedestals.
     Design of the connector layout within floor and wallboxes can minimize the plugging and unplugging of cables. Use of “pigtails” in these cases usually is avoided because of the risk of damaging cabling that is a part of the permanent room installation. Usually, connectors on plates within boxes are preferred. More robust cables and connectors are also used, often of the military-style multipin variety. In some cases where cables may present tripping hazards, connectors can be selected or modified to allow them to be unplugged easily. Often, audio XLR connectors are modified in this way, with their latches removed. Attention is also paid to the orientation of the cable with respect to the connection point, often requiring right-angle, swivel or other special connectors.

The Different Trades
     The design, logistics and contracts involved in installing furniture infrastructure are as important as the devices and mechanics themselves. Architects, interior designers and systems designers should be aware of the project schedule, labor conditions and special site conditions for the project before selecting furniture infrastructure components.
     Often, furniture with an integral connection system is selected before the technology team has discerned pro- ject parameters, and it may be difficult to adapt later. Although well-meaning interior designers may select furniture because of its technology features, the particular furniture infrastructure might be inappropriate or inadequate for the client’s requirements.
Once a system is selected and incorporated into the design, it is important that the purpose and special nature of these devices is communicated to the construction team. Many issues will arise, beginning with physical locations in the furniture, all the way to how cabling is managed from the furniture to the room. Although this issue may seem relatively trivial to the overall project, it should be discussed in both technology and architectural meetings, because so many trades are involved. These issues must be tracked on both project minutes and project schedules. Following are some of the concerns unique to each of these trades.

IT Issues
     The design of IT infrastructure in a building should follow very specific standards, yet be flexible enough to accommodate the space’s users and their technology needs. Designers select specific infrastructure components and cables for a variety of reasons, and attempt to standardize particular aspects of the hardware implementation. These building standards may include using a particular number of jacks on each wallplate, a particular number of patch points in each data closet cabinet, color-coded cables for different signal purposes, a combination of copper and fiber, etc.
     For example, a specific manufac- turer’s components might be used throughout the entire project, in the interest of “certifying” the bandwidth of each of the point-to-point cable runs. Most such system features are invisible to the casual observer, yet can strongly affect network performance. All must be accommodated by every infrastructure component, including furniture connectivity.
     Often, furniture infrastructure components are disliked by IT pros because of the challenges they present. Typically, they are specified by professionals other than IT, and the IT designers and integrators are expected, usually naively, to adapt to them.
A better approach is to use infrastructure components that can be configured with exactly the devices desired by IT designers. At the least, consistency of design, including patch point and sequencing standards, can be maintained from user endpoint to IDF (intermediate data frame) through MDF (main data frame). Ideally, system certification can be guaranteed.
     One frequent IT professional’s objection to furniture components is that they essentially represent an “extension cord” to the building infrastructure. Because the total cable distance between active network components is fixed by industry standard, bandwidth and distance certification should be tested at the furniture endpoint, not just at the wall- or floorplate endpoint. Nowhere is the need for high-quality components more important than in furniture infrastructure, because this represents a common point of failure for the system.

AV Issues
     AV designers have their own unique requirements for furniture connections. First, the connection points in the furniture likely will differ from location to location, if only in a small way. This is because all AV equipment does not use the same connector, and because different pieces of equipment typically are located at different points. Second, some AV signals are more sensitive to interference from adjacent cables than others, with microphone signals perhaps the most sensitive. This crosstalk could include leakage from improperly terminated connectors, or simply from close proximity to other cables (especially cables running in parallel).
     Third, AV connections must be labeled clearly to avoid confusion. Connection plates must have adequate room for this labeling. Finally, many AV connectors are deep and require space behind the plate not only for the connector but for the bend radius of the cable. This is true particularly for high-bandwidth coaxial cables.
     AV designers aim for systems with a minimum of connection points; each is a potential point of failure. Designers are also aware of the difficulties in adding new features to systems not prepared for them, requiring cable pulling and often the complete disassembly of connector plates. Value engineering processes on AV projects often mandate that some of the flexibility features be removed, but these decisions should be made carefully to avoid future complications and costs.

Millwork Issues
     Furniture with built-in cable management components presumably takes into account many of the described concepts. But when existing or new furniture is adapted with these infrastructure devices, the millworker could face myriad challenges. First, the location of the device might interfere with structural or decorative elements of the furniture. Second, the cable management components beneath the surface might require channeling and cutting to install raceways. Third, the legs or bases of the furniture might require that access holes and hatches be cut to allow users to connect to floorboxes below. Accommodations for a variety of power supplies, interfaces and cable excess must be made.
     Millworkers always prefer that any furniture modifications be made in their shops. This can be accomplished only with good project coordination. When standard furniture is used, or when furniture is modified in the field, the project team is open to mistakes, noise and dust, and labor issues.
     Responsibility for cutting holes, routing edges, installing trim, etc., should be left to professionals with the proper tools and expertise. If this means that millworkers are contracted separately just for this work, then these arrangements should be made. Damaged finishes, compromised structural integrity and mismatched hardware have both functional and aesthetic ramifications for the project.

Electrical Issues
     Electrical codes vary from country to country, but are fairly consistent in the United States. The NEC, or National Electrical Code, must be conformed to in order for the facility to receive a certificate of occupancy (CO). This critical document is issued only after an official inspection of the jobsite. Any electrical devices of an unusual nature, particularly those described here certainly will be scrutinized during inspections. Electrical engineers should be consulted to ensure that the power cabling from the ceiling or wall, all the way through the furniture and to powered devices, is configured properly.
     The juxtaposition of high- and low-voltage cabling is a common concern. In some jurisdictions, power cabling must be enclosed completely in rigid or flexible conduit. Rubber cord that can be construed as an extension cord often is not allowed. The furniture infrastructure device usually must be UL (Underwriter’s Laboratories) approved to pass fire codes. This issue is resolved in some devices by specifying only that the electrical contractor install a UL-approved standard electrical junction box. In any case, care should be taken to install the correct gauge wire corresponding to the circuit-breaker amperage rating.
    In all cases, the high-voltage and low-voltage cabling must be separated from each other physically. This can be as simple as installing a steel or rated plastic barrier between the cables and any terminations, but these barriers must pass inspection. In extreme cases, some electrical codes mandate that the low-voltage cabling in any devices that mix high and low voltages be rated for high voltage, typically 600V. This requirement should be understood before installation, because most AV cabling is not rated appropriately. In some cases, the cable will pass through a plenum air space, and both high- and low-voltage cabling will have to be plenum-rated, with a jacket made of Teflon or a similar material.

Construction Coordination Issues
    From this discussion, it is evident that the coordination of AV/IT furniture infrastructure devices must be tightly managed. It is appropriate that this be done by the general contractor because the final responsibility for the project typically lies with this entity. Because the “smart” furniture interacts with floors and ceilings, the general contractor must plan for these device locations as well.
     Often, structural elements such as floor ducts, beams, rebar, etc., dictate the relocation of devices. It may not be possible at all to install these devices into buildings constructed with prestressed concrete because the structural integrity of the slabs cannot be compromised. Relocation of the floor or wall interfaces could trigger a redesign of the furniture locations, which could in turn affect the design of the AV system!

Conclusion
     Use of furniture infrastructure devices for AV, IT and power connectivity is a convenient approach toward managing the multiplicity of cables required for AV-enabled spaces. But coordinating the installation of these devices requires a collaborative effort between members of both the design and construction teams on any project. Poor planning can result in excessive construction delays, and can affect many other trades such as carpet installers, painters and furniture movers. Proper planning can result in a highly functional, beautiful project, with hidden technology, proper equipment operation and satisfied users.

Joseph Bocchiaroo III, CTS-D, is a Principal Consultant with Electro-Media Design, Ltd., and manages the EMD Western New York office. Previously he was the AV Group Manager of a major NYC IT consulting firm. He is the Chair of the ICIA's ICAT (Council of Independent Consultants in AV Technology), a member of AECT (Association for Educational Communications and Technology), and a member of the Sound & Communications Technical Council.