Environmental noise is unwanted or harmful sound. This is commonly caused by human activities including road traffic, railways, air transport, industry, recreation and construction; and perceived in the near domestic environment such as residential areas, public spaces and community environments like schools (Kang 2013). Emitted noise in high-rise buildings could come from elevators, public facilities, sanitary system pipework, pressurized water supply and drainage systems. Though measures such as vibration damping and sound insulation have been attempted, a noisy indoor environment is still prominent in many high-rise buildings.
Outdoor noise could be the issue affecting the indoor acoustic environment. For example, opened windows can transfer outdoor noise into buildings. In naturally ventilated high-rise buildings, the sound pressure level increases with the floor level due to wind and air temperature influences (Dahlan 2009). Studies reveal that the
Fig. 4.2 The noise sources in high-rise buildings in China (Wang et al. 2012)
higher the level of the building, the level of noise received indoors increases (Liu et al. 2009). The high density of high-rise buildings magnifies the effect of noise and extends the time over which it is suffered. This phenomenon may be caused by the repeated reflection of sound waves between buildings (Wu 2007).
A survey from Wang et al. (2012) shows the main source of the noise in high-rise buildings (see Fig. 4.2).
From the figure we can see that eight sources have been regarded. Among that, outdoor traffic noise is regarded as the main source, which accounts for more than 50 %, followed by the on-site construction noise due to the urbanizations. Other noise sources include noisy neighbours, pets and facility systems.
The low-frequency noise will affect occupants’ working productivity and even health. The sound pressure level of low-frequency noise is much higher than that of high-frequency noise in the facilities room, and the attenuation performance of low-frequency noise is weaker than that of high-frequency noise in occupied rooms (Xu 2006).
Throughout the various physical layers of urban society, acoustics, or urban soundscapes, can impact on people’s physiological and psychological well-being. Undesirable noise can seriously degrade the experience of occupants living in problem locations or conversely, a well-designed urban environment that has considered its acoustic impact can bolster work productivity and general well-being through understanding the physical properties of form (Kang 2013).
Proper control over the noise and maintaining a comfortable acoustic environment is very important for occupants’ well-being in high-rise buildings. The noise control measures can be focused on buildings and service systems. Controlling noise in buildings includes fa?ade acoustic isolation, floor impact isolation, the design of party walls, waste pipes, entrance doors, in-sink garbage disposal units, road traffic and aircraft noise and pools above sensitive areas. Control over service systems includes mechanical plant, duct-generated noise, heat exchange pump rooms, fan-assisted variable air volume boxes, pool filtration plant, condensers and chilled water pipe systems, lift motor rooms, lifts travelling in lift shafts, garbage chutes, water supply pumps, standby power plant, SPA baths and pool vacuum cleaning systems (Palmer 2008).