When it comes to multi-family building acoustics, Hickman advises having an acoustical engineer on board to model and recommend an appropriate roof composition, and for architects to specify robust wall assemblies.
In its latest newsletter, Dialogue Now, Gensler predicts the work from home trend in a post-COVID era is here to stay. This may have residual effects on residential design, such as the need for an effective home office. In a WFH situation, the Four Work Modes—focus, collaborate, learn, and socialize—still apply and need to be addressed by the space, according to Gensler’s Tom Steidl and Brooks Howell.
“Multi-family residential buildings will need to be rethought, both in terms of dwelling units and communal amenity areas.”
The duo explores how to do this, while still addressing these four modes by considering real-life WFH situations. How to focus when kids are home? How to collaborate effectively on video calls when trying to hide a pile of dirty dishes in the background? Is a laptop propped up on a milk crate on the dining room table truly an ergonomic workstation?
As for non-children, pet, and spouse noise falling into the category of “Other,” Gensler’s workplace study points to research from the University of Illinois, which found a high level of noise (85 dB and above) reduces information processing and hurts creativity. Moderate ambient noise (70 dB) introduces enough stimulus to promote abstract processing and imaginative thinking. Three of Gensler’s 10 workplace acoustics strategies also apply to the planning, design, and construction of mixed-use environments in the post-COVID era of WFH: zoning, sound absorbing, and walls. These three strategies also correspond to the General Service Administration’s top three acoustic parameters used in acoustical design specifications: background noise, noise isolation, and sound absorption.
“As human beings we take care of things when it affects us, and there are so many noises at home: leaf blowers, lawn mowers, garbage trucks, even barking dogs,” says Sayali Wazalwar, acoustics researcher and specialist at GBBN Architects. “No matter what, these noises affect us especially in our WFH environments.”
Wazalwar offers several recommendations to remediate these unfortunate distractions. First and foremost, she says, be intentional in plans to use each space and organize adjacencies accordingly. In a home, examine the average level of sound, and have one declared ‘focus’ area in the home. Plan where doors are located with respect to those opening into a quieter area. Sealing a closed door, especially avoiding the gap under the door, will help to stop noise, suggests Wazalwar.
Throughout the core and shell, she suggests using double pane windows with gaps and sealants to absorb excess sound from exteriors. She also suggests creating an air gap in the wall cavity to discourage noise transfer from spreading downward into neighboring units. For instance, decoupled elastic false walls provide a reliable solution to effectively reduce airborne noise between rooms. Use drywall clips to stop structure-borne noise bridging the drywall and the false wall. Excellent building acoustic values can be achieved with these easy-to-install rubber and metal fasteners—even where little wall mass is available, such as a multi-family high-rise.
Another effective acoustic solution involves a dimpled flooring underlayment made from recycled tire rubber. It is designed to reduce the transmission of impact sound generated by footfall noise and is commonly used underneath solid and engineered hardwood floors, concrete, screed, and floating floor systems. It is available in multiple standard thicknesses (6 mm, 8 mm, 10 mm, 17 mm, and 25 mm [0.24 in., 0.31 in., 0.39 in., 0.67 in., and 0.98 in.]) which can be selected based on the application. Specifying this type of sound isolation material in the floor-to-ceiling assembly offers architects and acoustic engineers an advantage when it comes to design and structural flexibility and guarantees residents complete serenity.
