Measurement of Water Supply and Drainage Noise in Multi-residential Buildings

The water supply and drainage noise were investigated via field measurements. The measurements were conducted in the upper and lower floor bathrooms of two different structures that utilized the unit bathroom system. Psychoacoustics parameters, such as loudness, sharpness, fluctuation strength, roughness, tonality, auto correlation function (ACF), and interaural cross-correlation function (IACC) were also analyzed. We found that the Leq of the upper floor was higher than that of the lower floor over the total time period with 26.5 dBA difference in frequency 250 Hz to 2,500 Hz with a variation in the level with time. Furthermore, the differences in all the sound quality parameters except tonality and fluctuation strength between the two structures were higher than the just-noticeable difference (JND). Moreover, the ACF and IACF values of the lower floor bathrooms reduced as the distances from the bathrooms increased. This study suggests temporal variation in the psychoacoustic parameters may be the cause of noise nuisances reported by lower floor residents.