REDUCTION OF TONAL NOISE IN RESIDENTIAL BUILDINGS

Structure-borne noise in buildings is typically generated by machines and equipment that are not suitably isolated. A well-designed isolation strategy of the vibrating sources can effectively reduce the transmission of low frequency energy into acoustically protected spaces. Low-frequency noise, even in enclosed spaces, can increase the sound pressure level due to standing waves. The energy of the low-frequency waves can have a negative effect on residents, who often complain about headaches, irritability, migraine, fatigue, restlessness, insomnia, stress, and even depression. In solving problems with low frequency waves, it is important to identify the source of these waves, only then is it possible to design effective measures to reduce them. Measurements performed within housing units may not exceed noise levels defined by legislation. Despite this, residents often still complained of low rumbling noises. This problem was investigated by several firms over 5 years where the noise was thought to be coming from an external source. Based on this assumption, hired specialists attempted to reduce the transfer of noise through modifications to the facade of the residence. These however had little effect since the reality of the situation was that the source of the noise was coming from within the building itself, as later measurements had proven. Once the source of the low frequency noise was identified it was possible to establish effective measures in reducing the low frequency waves within acoustically protected spaces.