Building acoustics classification schemes in multifamily residential projects in the USA

In the USA, most building codes have lax requirements for airborne and impact sound isolation in multifamily residences, corresponding roughly to Class E or F in the COST Action TU0901 classification scheme. However there are segments of the market where housing developers are motivated to provide higher levels of sound isolation because occupant complaints due to poor acoustical isolation will reduce the rates that customers are willing to pay. The authors have worked with several large multifamily housing developers to develop separating wall and floor-ceiling assembly designs, and these have been repeatedly modified based on feedback from occupants. As part of the design process, a large number of field and laboratory tests were performed on these assemblies, allowing comparison between acoustical results and occupant satisfaction. Although limited to a subset of housing types and construction methods, an analysis of these tests defines a de facto classification scheme for airborne and impact isolation. The results are compared to existing classification schemes such as the COST action and the ICC Code+ Guidelines.