Most people readily acknowledge that cities are bustling, active and noisy places throughout the day. The allure for developers is to extend that vibrancy and activity into the night. Mixed-use developments help to accomplish this by combining retail, residential, and commercial uses in one exciting building or complex. But this dense, urban design poses several significant acoustical issues. How can a developer provide the excitement of street-level shops and restaurants while calming their noise and not impacting the late night office workers and high-end residences above them? How can architects design urban destinations that don’t disturb the neighbors upstairs?
Architects and acoustical consultants use several approaches to mitigate noise and create enhanced sound isolation between, above and below bustling and noise-sensitive spaces in mixed-use buildings. First, simple ideas such as locating noise-sensitive areas far from the sidewalk helps to shield them from outside noise, and placing mechanical systems on the rooftop or a lower level can address noise and vibration concerns. Non-sensitive uses can be placed between or around noisy spaces: for example, the Tufte Center at Emerson College has stacked theatres with a layer of offices in between, providing a buffer for the performance spaces. A concrete floating-slab floor also provides a substantial layer of acoustical isolation between spaces, although the cost and complexity of this sometimes makes it impractical. Finally, double wall construction and spring-isolated ceilings are popular choices for addressing concerns for noise transmission.
Consider Emerson College’s Paramount Center, a modern performing arts facility that is also home to some of the students who attend the liberal arts institution. The 180,000 sq. ft. mixed-use development is like a Jenga puzzle consisting of the 590-seat Paramount Theatre live performance venue, a 170-seat film screening room, a 200-seat black box theater, a sound stage, a scene/prop shop, rehearsal studios, six practice rooms, four classrooms, and 20 faculty offices; representing the top blocks of the “puzzle,” 60,000 sq. ft. of new residence space for housing 262 students fill the upper four floors of the nine-story complex. And let’s not overlook the 150-seat tenant restaurant on Washington Street and a dedicated student cafeteria on the lower level.
To make this exciting project with a broad range of programs work, the acoustical design of the entire facility was meticulously considered to provide all users – from the performers on stage to students sleeping and learning in their residence rooms – with an adequate level of sound isolation. On a typical campus, facilities such as residence halls, performance spaces, classrooms, and faculty offices would be in separate buildings with little to no acoustical interplay between the spaces. However, for the urban Paramount Center, all the program elements are tightly stacked – the black box theatre sits directly underneath the film screening room, which is directly next to the soundstage with a restaurant beneath it. With student housing capping off the building, livable acoustics were the biggest design challenge of the project. The design team devised clever ways of maintaining acoustical isolation between floors and rooms, adding concrete floating-slab floors, spring-isolated ceilings and double wall construction where appropriate.
University students are not the only residents in the city. Most residents of multi-residential buildings expect a reasonable level of privacy from their neighbors, but the residents and guests of the Mandarin Oriental, Boston expect a level of discretion and privacy found only at one of the most luxurious hotels and residences in Boston. Like the Paramount, the Mandarin facility houses a broad range of occupants ranging from the Residences at Mandarin Oriental, Boston, housing 50 ultra-luxury condo residences and 25 high-end apartments, to the ultra-luxe Mandarin Oriental, Boston hotel, with 136 guest rooms and 12 suites, encompassing a 16,000 square-foot spa and fitness center, meeting rooms, a ballroom, and Mandarin Oriental, Boston’s signature restaurant, Asana. Carved into the mix are exquisite retail spaces including the legendary Boston restaurant L’Espalier, along with Sel de la Terre, Mizu Salon, Frette linens and Gucci. Architecturally, this facility is like an extravagant wedding cake of luxury proportions, where sound isolation was critical for its success.
Given this high standard, the developer, design team and contractor understood the critical importance of succeeding with the acoustical constructions and concepts on the first try. The success of exceptional privacy and acoustical isolation at the Residences at Mandarin Oriental, Boston has provided the peace and solitude that residents have expected with this project.
To make exciting urban mixed-use projects function successfully, developers, designers and acoustical consultants need to work together to ensure that sound and impact isolation are addressed early in the design process and implemented properly during construction.
