Phoenix Noise & Vibration
5216 Chairmans Court, Suite 107
Frederick, Maryland 21703
Popular version of paper 2aAA9, “Challenges facing fitness center designers in multifamily buildings”
Presented Tuesday morning, November 3, 2015, 11:00 AM, Grand Ballroom 3
Session 2aAA, Acoustics of Multifamily Dwellings
170th ASA Meeting, Jacksonville
Transit centered living relies on amenities close to home; mixing multifamily residential units with professional, retail and commercial units on the same site. Use the nearby trains to get to work and out, but rely on the immediate neighborhood, even the lobby for errands and everyday needs. Transit centered living is appealing as it eliminates the need for sitting in traffic, seems good for the environment and adds a sense of security, aerobic health and time-saving convenience. Include an on-site fitness center and residents don’t even have to wear street clothes to get to their gym!
Developers know that a state-of-the-art fitness center is icing on their multifamily residence cake as far as attracting buyers. Gone is the little interior room with a couple treadmills and a stationary bike. Today’s designs include panoramic views, and enough ellipticals, free weights, weight & strength machines, and shower rooms to fill 2500-4000 square feet, not to mention the large classes offered with high energy music and an enthusiastic leader with a microphone. The increased focus on maintaining aerobic health, strength and mobility is fantastic, but the noise and vibration it generates? Not so great. Sometimes cooperative scheduling keeps the peace, but often residents will want to have access to their fitness center at all hours, so wise project leaders involve a noise control engineer early in the design process to develop a fitness center next to which everyone will want to live.
Remember the string and two empty cans? Stretch the string taut and conversations can travel the length of the string, but pinch the string and the system fails. As noise travels through all kinds of structures and through the air as well, it is the design goal of the noise and vibration experts to prevent that transmission. Airborne noise control can be effective using a combination of layered gypsum board, fiberglass batt insulation, concrete and resilient framing members that absorb the sound rather than transmit it through a wall or a floor/ceiling system. Controlling the structure borne noise and vibration can involve much thicker rubber mats, isolated concrete slabs and a design that incorporates the structural engineer’s input on stiffening the base building structure. And it’s not simply noise that the design is intended to restrict, it is silent, but annoying vibrations as well.
Reducing the floor shaking impact of dropping barbells on the ground is the opposite of hearing a pin drop. Heavy, steel plates loaded on a barbell, lifted 6-8 feet off the ground and then dropped. Repeatedly. Nobody wants to live under that, so designers think location, location, location. But big windows are pointless in the basement, so something has to go under the fitness center. Garage space, storage units or mechanical rooms won’t mind the calisthenics above them. And sometimes the overall design of the building structure, whether it be high-rise with underground parking, Texas wrap building (u-shaped building with elevated parking garage on interior.), or a podium style building can offer an ideal location for this healthy necessity.
It’s not an acoustical trade secret that the best method of noise control is at the source so consider what makes the noise. Manufacturers have met the demand for replacing the old standard graduated barbell steel plates for free weight combinations with a rubber/urethane coated steel weight. These weights make much less noise when impacting each other, but are still capable of generating excessive structure-borne noise levels. This is a great example of controlling both air borne (plates clanking together) and structure borne (barbells impacting the floor) transmission paths. Speakers and sound systems and the wall/floor/ceiling systems can work together to offer clarity and quality to listeners and limitations for what the neighbors will hear, but it takes expertise and attention.
Disregarding the recommendations of noise and vibration professionals can result in an annoying, on-site gym that brings stressful tension and ongoing conflict, nothing that promotes healthy well-being.
Foresight in design and attention to acoustical specs on building materials, under the direction of a noise and vibration engineer, assures a fitness center that is a pleasant, effective space for fitness and social opportunities, an asset to the transit centered neighborhood. Do everyone a favor and pay attention to good design and product specification early on; that’s sound advice.