The Effects of Acoustic Treatment on Plenum Windows in Reducing Outdoor Noise in Residential Buildings

The growing housing need and redevelopment of old urban district in Hong Kong made building residential flats in busy districts unavoidable. These high-rise residential developments are usually bounded by roads with busy traffic, railway tracks or even surrounded by fixed noise source. Traditional mitigation measures like building set back, adjusting building orientations, acoustic fins and etc are no longer sufficient to tackle these problem so as to create a comfortable environment for future residents. Plenum windows have been used as innovative measures to reduce traffic noise in the past decade. Nowadays, they are also used in mitigating railway noise or even fixed noise which require different noise reduction characteristic and enhanced performance. To enhance the noise reduction performance of the plenum windows, different kinds of absorption treatment are used and tested: micro-perforated absorbers are added to the inner side of the sliding panel while perforated absorptive panels are added to the inner edges of the window plenum. Noise reduction performance of plenum windows with and without treatment are compared. The effects in noise reduction of implementing these treatment to plenum windows is being studied by comparing the measurement results in this paper.