Reduction in reverberation time, resulting from a unique acoustic treatment behind the final surface layer of drywall

Abstract

When sound energy generated in room strikes a surface, it is partially reflected, transmitted, and absorbed. This is true for each layer of material in a wall, ceiling, or floor. The wave interaction with the surface depends on many factors. The main factors that are typically involved in calculations of reverberation time are the frequencies of concern, the rigidity and density of the surfaces, and the absorption of various objects in the room. This paper presents results that show the importance of considering the composition of the surface (wall, floor, or ceiling) including materials located behind the exposed surfaces. Specifically, it will be demonstrated that a properly installed layer of a loaded vinyl sheeting under the final wall surface layer of drywall will produce a significant reduction in the room reverberation time. With this technique, the preferred reverberation time can be achieved more naturally, while accommodating design constraints such as washable surfaces and minimizing the amount of additional surface treatments required. An additional benefit in the use of the loaded vinyl product behind the surface is a significant improvement in the STC of the wall or ceiling in which it was installed. © 2013 Acoustical Society of America.