Case study of acoustics in two very large atriums Free

Two recent projects have involved very large spaces with predominantly hard finishes. One assignment was to develop an acoustic treatment plan for an existing six story interior courtyard within an office tower. This space, a very formal design finished in marble, wood paneling, and glass, had a 7 second reverberation time. The courtyard was available as a lounge space to all tenants of the building but was barely utilized. We were part of a design team hired by the building owners to update the courtyard and make it more user friendly, including improvement in the acoustics. The other atrium was part of a new project—a seven story glass enclosure with a concrete floor. This atrium serves many different functions including the main entrance and security lobby, dining space, informal meeting space, and lounge. The acoustics were mitigated by the irregular shape, areas of carpet on the balconies, and limited areas of acoustic paneling. The new atrium is a success and it has become the living room and hub for this large building. It is well used throughout the work day for all of the purposes mentioned above and more. Renovations for the other space are still in design as of the abstract deadline, but there may be finished in time for the Spring ASA meeting. The presentation will include a discussion of the dimensions and finishes, acoustic priorities, design challenges, acoustic measurements, and subjective comments.