ABSTRACT
Foliage and hedges have many important functions for our environment, especially in densely populated urban environments. They produce oxygen, purify the air, and serve as visual aesthetic elements, windbreaks, and habitats for birds and insects. Plants grown on a building façade (Figure 3.1) contribute to balanced microclimate by their ability to store humidity. However, plants are rarely used for noise control in urban development because it has long been believed that they possess no useful acoustical properties. The aim of the research presented in this chapter is to investigate the potential of using plants in noise control elements and to determine
those characteristics of plants that make them particularly good in terms of their sound absorption and transmission properties. The reported investigations have been performed under controlled laboratory conditions as well as outdoors. In addition, theoretical and empirical models have been adopted and applied to explain the observed attenuation and absorption coefcients and to predict the acoustic properties of plants when used as a part of urban and landscape architecture.
