The Effect of Shading Louvers and Compact Silencers as Noise Barriers in a Ventilated Double Skin Façade

Abstract

Among environmental stressors, urban noise exposure has become a critical factor for building occupants’ health along with rapid urban population growth. The World Health Organization (WHO) has warned that high external noise levels can cause numerous health problems such as sleep disturbance, high blood pressure, and psycho-physiological symptoms. Road traffic noise, among other urban noise sources, has been regarded as the major constraint degrading the acoustical quality of urban environments. However, it was found that there is a conflict between ventilation performance and noise transmission in naturally-ventilated buildings in urban areas. Therefore, this research topic aims to explain the effect of shading louvers and compact silencers as noise barriers in ventilated buildings for indoor air quality and acoustical quality. This study is intended to investigate the multidimensional aspects needed to improve ventilation potentials and acoustical performance using a double skin facade (DSF) which is composed of an air cavity, two layers of glass, shading louvers, and air vents. This study employs a mixed-use research method composed of a preliminary simulation study and an experimental study. The preliminary simulation study focused on the ventilation performance of a DSF using computational fluid dynamics (CFD) software, and then an experimental study was designed to measure noise reduction of a DSF mock-up in a reverberation chamber based on shading louver orientation, type, and surface material, and the percentage of air vent open surface area of a DSF. Research findings suggest that shading louvers and compact silencers are effective in noise reduction of a DSF. It implies that integrated shading louvers with sound absorbing materials and compact silencers for air vents can reduce noise transmission through ventilation openings in naturally-ventilated buildings.