Windows can be the weak link in the transmission of unwanted sound into a building. Just as a window lets in the light, it can also transmit unwanted noise. To establish the desirable acoustical environment, the noise control requirements and the sound-reducing properties of glazing materials should be considered as an integral part of the total space design.

Laminated glass is highly effective in reducing unwanted sound transmission, and laminated glass can be used in standard window design.

The acoustical performance of laminated glass is the result of the sheer damping (sound deadening) characteristics of the plastic interlayer. Since sounds are actually a combination of acoustical energy at different frequencies, effective sound control requires that the sound level be reduced across a wide range of frequencies. Truck traffic is typical of a low-frequency noise source, while speech and typewriters are of a middle frequency, and jet aircraft and industrial equipment of a higher frequency.

Laminated architectural glass effectively reduces the coincidence dip in 1,000 to 2,000 Hertz range common to glass products. Coincidence impairs the overall acoustical performance of glazing systems, since general environmental noise sources such as traffic and aircraft, have significant amounts of sound energy in this frequency range.


To provide a single number rating for describing the sound isolation performance of a material, the ASTM has developed the sound transmission class, or STC rating.

STC is measured in decibels (dB), derived from individual transmission losses at specific test frequencies, (ASTM E-90, ASTM E-413). It allows a preliminary comparison of the performance of various glazing materials. Final glazing selection should be based on a comparison of transmission loss (TL) performances at all frequencies of the actual sound spectrum to be controlled.


Less noise means better value for residential home-owners who want to enjoy watching television, listening to music, and spending quiet time. Noise reduction reduces stress levels and permits people to be more productive, creative, and comfortable, while enjoying improved privacy.

Sound transmission loss (TL) of a panel is the difference in decibels (dB), between sound energy incident on a panel and the sound energy transmitted through the panel . The more effective the sound isolation provided by the material, the greater the TL.
       
       
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