Yakov Jacobson / October 16, 2016 / Industry News
Window Glass Acoustics
Noise is one of the common issues when glass is installed in a building. Regular glass windows transmit sound and make it harder to drown out noise from the outside, which can be from traffic, crowds, or construction work in the neighborhood. This is why we have acoustic windows made out of noise reduction glass. There are many window options you can choose from, depending on the intended acoustic performance. It all comes down to the combination of the components used in the glass.
These are considered a practical way to achieve noise control in a frequently loud neighborhood. The best thing about dual pane windows is that they are cost effective, and energy efficient if they come with Low-E glass. Also, they uphold the aesthetics of the structure while providing functionality. Standard dual pane windows have an STC rating of about 27, but there are also types with STC of up to 34.
Glass panes of the same thickness can have a limit to the frequencies of noise they keep out. A dual pane window with glass panes of the same thickness might sometimes not be enough for the level of noise reduction you have in mind.
One example of dissimilar glass combination is where the thickness of one of the panes is twice that of the other. Each pane blocks different frequencies of sound. While one deters low-frequency sounds, the other takes care of the higher frequencies sounds such as screaming. As a result, acoustic windows of this type can block out a greater range of frequencies, and would have significantly higher STC ratings that standard dual pane window glass.
From the improvement in performance detailed above, you would think that progressively, triple pane windows would certainly be better than a single pane. This is not necessarily true though. For one thing, a triple-pane window would have small air spaces between the panes, which are not favorable where noise control is concerned.
These spaces can create a reverberation in the sound waves, amplifying the level of sound and counteracting the acoustic application of the window. Testing shows that triple pane glass has just a over the STC rating of dual-paned dissimilar glass.
These are some of the glass types used for noise reduction. You also have laminated glass, which doesn’t score much higher on STC compared to dual-pane dissimilar glass, and actually costs more to install