Facade Noise Attenuation through Curtainwall Glazing: Measurements, Analysis and Audio Simulations

A case study of an acoustical consulting project involving the design of a state-of-the-art, neuroscience research & education facility located less than 100 feet from an above-ground subway line in New York City. A principle acoustic design concern was airborne noise transmission through the curtain wall façade construction into laboratory, office & classroom spaces. Simultaneous sound pressure level measurements and binaural audio recordings were conducted at the site for numerous train noise events. These measurements and recordings were repeated after scheduled track maintenance was completed which had replaced existing rail connections with resilient elements. Using transmission loss test data for various glass configurations, analytical estimates of interior noise levels were developed. Audio simulations were created by electronically filtering the recordings according to transmission loss data for each glass configuration. These simulations were used to demonstrate for the client the effects of varying levels of façade attenuation provided by a range of glazing construction options. Near the completion of the project, simultaneous sound pressure level measurement audio recordings were repeated inside the building and compared with the previous estimates and simulations.