Prediction of sound insulation for middle class apartment based on noise site analysis

As a middle-class apartment in Indonesia, Rusunami are commonly found in urban area that are exposed by noise pollution from traffic road and railways. Sound insulation for building envelope is therefore needed to avoid the building occupants from acoustical comfort problems (i.e. health and psychological effects) due to the exposure of high sound intensity. By using result of the noise-site analysis, this study aims to propose the Sound Transmission Class (STC) for building envelope. Materials and its layers were modeled using Insul to obtain Transmission Loss (TL) value of which further calculation to result the STC value. Investigation of sound propagation were modeled and simulated using acoustics pressure module in finite element based-software. The noise reduction inside Rusunami was calculated based on EN 12354-3: 2000 using the outdoor to indoor calculation. The indoor SPL was further compared to the noise standard on the indoor residential area of 45 dBA. The result revealed that the wall with 110 mm thick concrete material with a layers of 15 mm cement sand and 5 mm plaster could provide STC 53 and indoor SPL 37.72 dBA while lightweight concrete material with same thickness and layers could produce STC 49 and indoor SPL 41.39 dBA. The use of both materials as building envelope for Rusunami have been in accordance with the standard of noise level. They have been identified as requisite to protect public health and welfare with an adequate margin of safety for indoor residential area.