Student housing series: How do you balance affordability and comfort in acoustical design?
May 21, 2018
May 21, 2018
Recognizing the source of noise in student housing guides acoustical and sound deadening elements that have the greatest impact
Good acoustical design is important in any type of project, but it becomes a top priority in housing. Housing is where we relax, eat, and, most importantly, sleep. However, with concerns over affordability driving many of the design decisions in student housing, it becomes uniquely difficult to maintain good acoustical design while keeping costs low. Recognizing the source of noises from a student resident population allows us to spend money on acoustical and sound deadening elements that have the greatest impact.
Residents of a student housing building are unlike those of traditional multi-family. Without families or children to worry about, these buildings have much more common space that encourage social interaction and development. Broken down by age, freshmen have more group study and socializing outside of their unit than upperclassmen. This is due not only to maturity levels and academic curriculum, but also the style of unit and the amount of internal living space provided within.
Students who enjoy frequent social interaction will tolerate higher noise levels than that of a family where privacy is a top concern. This does not mean students will tolerate loudness, only some rambunctiousness.
In student housing, it becomes uniquely difficult to maintain good acoustical design while keeping costs low.
Students frequently live with up to five other students within their own unit. These are students with different lifestyles, interests, and ideas of what is “loud.” Most noise complaints from students trying to sleep come from roommates, not adjacent units. This allows designers to place less focus on stopping all sound between units as opposed to multifamily housing where it would be a top priority.
While typically quiet, study areas foster conversation between residents that often runs late at night. If the design permits, it’s advisable to avoid placing bedrooms adjacent to studies. If not, the acoustical protection required by code is typically adequate to accommodate these spaces. In lounges, the source of sound is greater and harder to control as there may be a sound system or TV included. Additional acoustical protection must be provided to prevent sound transmission.
In building amenity spaces, the first floor of student residences typically features loud community space and circulation with units placed above. This building community space needs sound-isolating material or protection for units above. If a fitness room is included, it is strongly encouraged to not place it over units due to impact sounds and the high cost of mitigation.
Parity of space is a central element to student housing. Each student of the same class pays for and expects the same size bedroom, living room, and access to community spaces. This encourages a building type where floors stack. Units sit on top of units, community space on top of community space. In terms of acoustics, this affords us the luxury to assume that the noise level in a space above another is within the same range. Impact Isolation Class (IIC) describes sound from impacts as opposed to Sound Transmission Class (STC) describes sound from noise through the air. Stacking allows us to typically provide the code minimum IIC requirements.
Sound from impact can still travel laterally however, like from a corridor to a unit, or community space to a unit. In corridors, we try to use carpet tile in lieu of hard surface because it provides a finish surface that deadens sound while a hard surface would require an additional acoustical membrane.
To protect the units above from building community space on the first level, we use sound clouds, acoustical tile, sound-absorbent fabrics, flooring, or area rugs. With typical floors, the concern is noise through air traveling laterally. In community lounges, we provide a wall assembly with a higher STC rating. This can include an extra layer or drywall or acoustical sound isolation clip instead of resilient channel. Stairs are a particularly large source of noise from residents communicating between floors, so we often provide a double wall.
The unique challenges posed by controlling acoustics of student housing buildings presents designers with the opportunity to decide how and where we chose to mitigate sound. With creative methods, materials, and application, we can solve the sound problem economically while providing students with a socially collaborative experience they will carry with them throughout their academic life.
This is the second blog in a multi-part series on technical aspects of student housing design. The next blog will focus on the right questions to ask before designing student housing.