Controlling sound transmission is a key aspect in the design of any new facility, and, in addition to visual privacy and security, is an important concern. The following are some basic guidelines.

• For conference-type rooms where sound control is necessary, specify walls constructed from the floor to the structural deck of the floor above, and include sound-absorbing insulation between the wall studs. Staggered stud, unbalanced design is recommended.
• Even floor-to-deck staggered stud walls must have at least one large hole, perhaps two openings (one at each end) to provide for return airflow, and these become perfect conduits for transmission of conversation. This condition can be addressed by installing acoustical traps – short, ducted returns – on the conference room side of the openings required for return air. Often these traps can be constructed of a ridged acoustical board, about five feet long, with one right angle bend. A well-engineered and constructed acoustical trap should absorb most conversations, yet be large enough to permit sufficient return airflow.
• Supply air ducts are often insulated to prevent heat or cooling loss. The thermal insulation may also provide some added security benefit by absorbing sound and preventing conversations from being overheard in adjacent rooms.
• Depending on the assessed needs of occupants, consider locating spaces where sound control is critical in areas without windows or with limited windows to the outdoors. High-tech listening devices are capable of picking up conversations through windows from a distance of 1,500 feet away. Although such eavesdropping may be unlikely, some thought should be given in facility design to the nature of the occupants’ needs and the sensitivity of information and business housed within.
• If windows are indeed part of the design, consider providing protective drapes, which can help mask sound, and well as serve as visual privacy barriers when needed. White noise generators can also be connected to windows or directed at them to help maintain sound control.

The author of this article, David D. Owen, is founder of David D. Owen Associates, a facilities management and real estate consulting firm that focuses on development consulting for corporate and personal investment clients. He is experienced in programming design, construction, furnishing, and security system design and implementation. David has described how to implement building security strategies in his book, Building Security: Strategies and Costs.