Gymnasium Noise and Vibration
Sound Solution Consultants (SSC) were approached by managing agents of a mixed-use, multi-storey building, regarding noise and vibration issues from a ground floor gymnasium. Noise complaints had been lodged from tenants in several flats immediately above. The scope of works included fault finding investigations to determine the cause of the disturbance and provide a commensurate noise control solution.
A series of practical tests were carried out within the ground floor gymnasium and residential flats above by dropping weights on the gymnasium floor and reviewing the acoustic effect. The issue experienced in flats above concerned excessive vibration and re-radiated, structure-borne noise; above common thresholds that describe human response to sound and vibration, relating in a quantifiable disturbance, annoyance and complaint. The results of the testing supported disgruntled comments from residents above the gymnasium.
Accredited airborne sound insulation measurements were also undertaken between the gymnasium and residential rooms that demonstrated very high separating floor performance in its current state. The problem was therefore not deemed to relate to the sound insulation of separating or flanking elements.
The solution to the problem was to install a heavyweight floating-floor system, designed to reduce the energy travelling through the building structure because of weights being dropped in the gym. A sample of the proposed floor system was tested within the gym that confirmed that the proposed solution was able to mitigate a significant proportion of the energy transferring to the structure and flats above. A conclusive result was achieved whereby the engineered solution reduced the vibrations to a level barely noticeable within the flat directly above the gymnasium.
The final floating floor system, provided by Mason UK Ltd, consisted of a 100 mm thick, floating concrete slab with appropriate floor finishing, mounted on helical spring isolators designed to reduce vibration induced into the gymnasium floor. The heavy-weight floating floor system was isolated from the gymnasium walls, limiting the transmission of vibration to the rest of the building.
As part of the technical works and vibration analysis, SSC provided the floating floor supplier with detailed technical information describing the reduction in vibration that was achieved in-situ from the test sample. Impulse response information was provided in the time domain with low frequency (FFT) responses; demonstrating the magnitude of spectral improvement that would result from the technical proposal.
To date, following the installation of the heavy-weight floating floor system, it is understood that complaint of noise and vibration from ground-floor gymnasium use has been resolved in the residential flats above.