Gym noise and vibration

Accessible exercise vs noise

As the accessibility for exercise has grown over the past few decades, so has the demand for gyms local to the places where we live, work and socialise. Very often, these are built in to residential apartment buildings, office buildings and retail destinations. Gyms and fitness centres can be noisy spaces and controlling noise and vibration transfer to more sensitive areas should be a key consideration.

Is your spin class loud enough? (noise sources)

For a spin class to be motivational and successful (and enjoyable), the amplified music needs to be loud to immerse participants in the activity. Often this requires music levels akin to that in a busy bar or night-club. When located in mixed use noise sensitive buildings, there is potential for causing disturbance. Other noise sources such as the background music in the gym, noise generated from the use of the cardio equipment, resistance machines, and other assorted gym activities would also need to be considered.

Are your weights heavy enough? (vibration sources)

Vibration is easiest explained as the tactile perception of sound in a solid material. With that in mind there are a number of activities in a gym that have the potential to generate vibration within the building, namely: footfall on a treadmill, footfall from an aerobics class, weights dropping within resistance machines and most problematically free weights being dropped. Heavier weights impart a larger force on the floor and generate higher vibration levels. Like the noise sources, these all have the potential to cause disturbance to those in adjacent spaces. Rather than tactile vibration transfer, the issue is typically vibration entering the building structure, and manifesting itself as sound within the adjacent spaces. This is termed structure-borne sound.

Sharing a building

To successfully allow a building to be shared between different uses, it is important to establish suitable noise and vibration transfer criteria. These are typically based on the use of the adjacent spaces (apartments, offices, retail, etc) and the gym operating time (daytime or night-time).

Noise transfer criteria in the adjacent spaces can be set in terms of:

  • Average sound pressure level – LAeq (dB)
  • Maximum sound pressure level – LAFmax (dB)

When structure borne noise transfer is controlled, it is unlikely that vibration transfer will be an issue. Suitable criteria can still be set though in terms of a vibration dose value (VDV), or average, or maximum RMS acceleration values.

Solving the problem

To control noise and vibration transfer, the proposed activities within the gym must first be understood. This can be through reviewing layouts and discussing proposals with designer or operator. A visit to a similar existing gym is always a good idea if there are any novel activities that need to be understood or measured (if the operator happens to run gyms in a few locations).

The next step depends on whether the proposed space for the gym is in an existing building or part of the proposals for a new build.

  • If the proposed gym space and adjacencies are in an existing building, preliminary acoustic testing can be carried out. This would typically involve measuring the airborne sound insulation of separating constructions (ie, floors and walls) and measuring the structure-borne noise transfer from vibration generating activities.
  • If the spaces are in the planning or design stages, predictions of noise and vibration transfer can be carried out. Though if the gym forms part of the fit-out of a new building, there is sometimes the opportunity to carry out testing of the space, once the shell and core is complete.

The on-site and/or desktop assessment will inform the existing level of sound insulation and anticipated structure-borne noise transfer from the proposed activities. This allows appropriate mitigation to be integrated into the design. The mitigation measures can include resilient layers, floated lightweight or heavyweight floors, suspended ceilings, enhancements to the building facade, enhancements to base build/shell and core partitions.

The main goal of acoustic engineering input in this scenario is to allow gyms to easily coexist within noise sensitive spaces.

By Matt Robinson
PhD, BSc, CEng, MIOA