Acoustic trends in housing relative to major trends in real estate

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Three major trends are emerging in real estate that directly affect the acoustic requirements of a home or multi-family. On the surface these trends appear to be dissimilar, however each has a common thread when considering the required acoustic engineering of the space.

The first trend in real estate involves young couples who are starting a family and/or individuals/couples who are transitioning from a very small inexpensive apartment or condo. Typically acoustic disturbances, such as footfall from above and sound through the wall or ceiling from their neighboring tenants, was commonplace. As they move into more expensive rentals or purchase their first home, eliminating this level of disturbance is now important criteria when evaluating a residence.

The second trend is at the other end of the real estate spectrum, where baby boomers are downsizing and moving into smaller or multi-family homes. Usually, they are selling a spacious home. Architects and builders are trying to create an environment where the floors and walls are constructed to prevent  the sounds of  neighbors from disturbing the occupant. In the past, this was a lesser issue since walls were only shared with a family member, if anyone. Privacy is becoming a critical aspect of acoustic design whether it is a smaller home, or a multi-family.

The third trend is that friends, instead of choosing to move into a senior housing facility, have opted to build or renovate a home together where they can share that home in a multi-family setting. The plan is to either create their own housing system since it is more desirable to share a space with friends rather than sharing a residence with someone they do not know.  There are numerous variations to this trend. The outcome of which can be a majestic estate, one example is the multi-family estate designed by Brion Jeannette’s office, Aerie, in Corona Del Mar, CA. On this project, great attention was given to the acoustic separation of floors and walls. Additionally, a lot of thought was put into inhibiting plumbing sounds from one residence to another.

These three trends have similar acoustic construction requirements of privacy and comfort. The floors need to be engineered so they do not transmit disturbing footfall. The floors and walls also need to be capable of stopping elevated sound. Architects have training in designing walls that meet a certain sound transmission class (STC). The STC that was part of the past design is  no longer an acceptable goal since today’s modern TVs have strong base frequency response.   The floors and walls all have to be able to stop this low-frequency sound whether it is coming from a room that is closer than it used to be, or an apartment. Previously, the need to stop the disturbance was less urgent since it occurred in one’s own home amongst family. With multi-family housing and apartments, the need to silence bothersome acoustic disturbances is greater. Plumbing and HVAC noise also need to be addressed.

A Canadian national lab  conducted a study that demonstrated how the STC of a ceiling, floor or wall can be reduced due to a small hole by as much as 10 STC points. This small acoustic leakage and STC reduction can be the result of an electric outlet, recessed light, etc. that is not acoustically treated. The STC reduction is typically the difference between hearing or not hearing the person in the adjacent room or floor. When that person is not a family member, it becomes more disturbing.

One of the biggest problems trying to achieve a complete acoustic seal in a wall or floor so that there are no holes is that typically the hole is not visible. An example is that after an installation of a layer of drywall it is possible that there could be a small acoustic leak at the seam where the wall board meets the floor or ceiling. There needed to be a method by which this was tested. The solution was a 2011 patent on a device that tests a wall, floor configuration or pipe or HVAC duct that is wrapped in order to confirm that the installation was correct. This device is used by acoustic installation crews of SoundSense.

The last acoustic trend is associated with the design trend for larger volume as well as curtain and carpet free spaces. These spaces have a high reverberation time or become an extremely echoic space. Every enclosed space exhibits reverberation. Reverberation is sound persistence due to repeated boundary reflections after the source of the sound stops. Due to overlapping of successive syllables or tones, excessive reverberation reduces the intelligibility of speech and music within a room. On the other hand, too little reverberation will make the room “dead.” The ideal reverberation time for a room varies considerably and depends on several factors, including but not limited to: personal preference, volume and auditory requirements.  

SoundSense corrects reverberation in a room by mathematically positioning and applying acoustic material at precise locations on the boundaries of the room. SoundSense identifies the optimal locations for this acoustic treatment by means of its proprietary computer program that delivers The Paradise 

Effect™, an acoustically refined environment where pure tones are enhanced, speech is clear and the room gives a feel of general well-being.

Clearly, reverberation treatment is critical in rooms intended for any type of audio application such as the media room, family room, exercise room, or any area intended for general TV/audio listening. Tuning reverberation should also be addressed in potentially echoic rooms such as the dining room. In addition any room intended for reading, learning, or working should receive reverberation treatment. Ideal reverberation not only improves productivity and concentration, but also provides a positive living environment.

All in all, the acoustic design of a space is becoming more relevant in real estate. Buyers are acoustically sensitive depending on their property history. Being able to recognize these needs and address them properly will help ensure every client gets the home of their dreams.

Dr. Bonnie Schnitta is the founder and CEO of SoundSense, LLC,  a turnkey acoustical consulting and engineering company that also offers a complete line of acoustic products, experienced installation crews, and construction consulting. 

To view the original article please see our magazine titled “Break it Down” Vol 3, Issue 6 by Clicking Here