Explore STC Window Ratings


STC Window Ratings

STC window ratings measure the amount of sound that passes through a window. STC is perhaps the most important performance rating for a soundproof window and an excellent way to compare soundproof windows to one another.

Soundproof Options
Frame Material
Window Quality
Type Of Installation
Number Of Windows
Zip Code

STC Window Basics

STC stands for sound transmission class and, in terms of home windows, is a number that ranges from 18 to 54. STC ratings are similar to the Richter scale in that a small increase in the STC number is actually considerably more effective in stopping sound from entering. Sound transmission class increases by employing tried-and-true techniques used to soundproof windows, including a wider frame for larger gaps between the panes of glass, different thicknesses in each pane of glass and solid construction and seals used in the glazing process.

Sample STC Window Ratings

A standard single glazed window will have an STC rating of 26. A standard dual pane window will have an STC rating of 29. A standard triple pane window will have a STC rating of 33. Finally, a standard double paned window with laminated glass will have an STC rating of 38. A high-quality soundproof window will have an STC rating around 42. The best soundproof windows will have an STC rating of 48.

STC Window Rating Examples

Here are some real world examples of windows and their STC ratings.

Harvey Slimline STC: 28
Viwinco OceanView Window STC: 34
Indow Acoustic STC: 38
Milgard Quiet Line STC: 46

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