Analysis of the effects on transmission loss of number of layers and properties of gypsum panels in stud walls

The authors and colleagues have performed several laboratory testing programs on stud walls to systematically investigate the effects on changes in wall type. In previous work [Proceedings of Internoise 2015, paper 676], the authors analyzed the effects on third-octave transmission loss of changes to stud configuration. The authors perform additional analysis of the effects of changing the number of layers of gypsum board on the assembly. Beyond the number of layers, the investigation includes other factors such as the variability between panels of the same nominal size and type, effects of "damped drywall" (composite panels with viscoelastic damping), and lightweight gypsum panels with the same fire rating but lower mass. The results may be useful for predicting the effects of changes in wall design and for constraining theoretical models of stud walls.