A rating of the ability of an interior partition to attenuate sound, measured by the amount of decibel (dB) noise reduction at different sound frequencies. In essence, it reflects the noise reduction that the partition can provide. The STC for monolithic ¼” (6 mm) glass is approx. 31-32. The same thickness standard laminated glass is approx. STC 34, while Bendheim’s +2 Acoustic Glass has STC 36 at ¼” thickness. Bendheim’s uninsulated 4.5”-thick channel glass walls have STC 38; our insulated 4.5” channel glass walls reach STC 43. The STC rating of a standard 4.5” uninsulated stud wall is approximately 33. Lamination, particularly using specialized acoustic interlayers, significantly improves the glass STC; increased panel thickness can also enhance sound control.

STC measurements are derived by testing in accordance with ASTM E90, “Laboratory Measurement of Airborne Sound Transmission of Building Partitions.” STC values are attained by applying the Transmission loss (TL) values to the STC reference contour of ASTM E413, “Determination of Sound Transmission Class.”