The influence of the wall cavity on the transmission loss of wall systems - experimental trends

Numerous experimental investigations have been conducted into the sound transmission loss of double leaf wall systems. From these investigations, it has been observed that the properties of the wall panels, material placed within the wall cavity as well as the type of wall connections used, greatly influence the sound transmission through the wall system. In all of these cases the wall cavity greatly affects the extent of this influence and in some cases it can even nullify their effect when changes are made. In this paper the influence of the wall cavity based on experimental trends is investigated. The investigation revealed that a wide variety of conclusions were obtained by different researchers concerning the role of the cavity and the properties of any associated sound absorption material on the sound transmission loss through double leaf wall systems. Consequently recommendations about the ways in which sound transmission through cavity systems can be improved should always be qualified with regard to the specific frequency range of interest, type of sound absorption material, wall panel and stud characteristics.