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Effect of Perforated Ceilings on the Floor Impact Noise in Multi-Storied Residential Buildings

In this study the effect of a perforated ceiling on the floor impact noise was investigated. Although a ceiling with an air cavity is effective in the reduction of noise, the level of heavy-weight floor impact sounds might also be increased. In order to determine whether this is the case, various ceilings were constructed with differing levels of perforation, and the sound pressure level due to impact noise was measured. We show that a ceiling without perforation led to an increase in the level of heavy-weight floor impact sound of around 5 dB, whereas a perforation ratio greater than 0.8% did not increase this level. Based on these measurements, commercial perforated ceilings that are applicable to actual residential buildings were designed, and the reduction of floor impact noise was verified.