In-situ investigation of multi-perforated gypsum boards in an apartment living space for reduction of heavy-weight impact noise

In this study, effects of multi-perforated gypsum boards on floor impact noises were investigated in a box-type test building and an actual apartment building. In a box-type test building with 150-mm thick slab, various design factors such as hole pattern, hole size, opening ratio, backing or finishing materials were considered. Heavy-weight impact sources of bang machine and rubber ball were employed. Test procedure followed KS F 2810-2, then single number rating was derived in accordance with KS F 2863-2. As results, reduction of heavy-weight impact noise by applying multi-perforated gypsum boards as a ceiling material was expected maximumly up to 3 dB for bang machine and 5 dB for rubber ball, respectively. Installation amount was the dominant factor to reduce impact noises at the frequencies above 125 Hz rather than installation location or profile design. Then, in-situ investigation using standard impact sources and 5 children was carried out in an actual living space of actual apartment dwelling unit. Comparing before and after installation of multi-perforated gypsum board, 1 to 2 dB of heavy-weight impact noises were reduced. In addition, subjective impressions of the reduced impact noise were discussed based on the field questionnaire survey using actual children' running situation.