An Electronic Database of Façade Sound Isolation

In late 1960's, the Centre Scientifique et Technique du Bâtiment (CSTB) of France sponsored a controlled field experiment to determine the exterior-to-interior sound isolation of a building façade. The CSTB report was later translated by the U.K. Building Research Station and subsequently issued by the U.S. National Bureau of Standards as a Technical Note entitled, "An Investigation of the Protection of Dwellings From External Noise Through Façade Walls". This 50-year-old French study is arguably the most comprehensive investigation of façade sound isolation in the open literature. It contains sound isolation data measured in 16 one-third-octave bands for two types of window systems and six balcony configurations. For each façade condition, a calibrated sound source was oriented at a number of discrete angles in both azimuth and elevation. The measured data were originally plotted in 13 figures comprising 2700 individual data values. The data have been manually extracted from these plots and assembled as an electronic database. The electronic database is now available for unrestricted use by the acoustical community. The paper describes the experimental façade configurations, summarizes sound insulation theory, and describes some applications.