Why are STC ratings important?

03/14/2023

As people seek to be closer to loud but job-rich city centers or noisy transportation hubs such as freeways and train stations, reducing commute times and gas costs, developers are turning to acoustic windows and doors to block those urban noises and create a quiet, peaceful, and comfortable interior space.

The Sound Transmission Class (STC) rating system was developed in the 1960s as a way to compare how well doors, windows, walls, and ceilings act as sound barriers and the rating system continues to be updated to meet modern standards.

▪ STC determines the level of sound that can move from one room, through the product in question to another room. The more effectively the sound is blocked, and transmission is reduced, the higher the score.

▪ STC ratings are often used to select and compare products needed to achieve the desired outcome. For example, a hotel with a highway on one side and a lake on the other may choose products with the score best suited to optimize the respective conditions.

▪ STC scores are calculated on product samples in certified labs over the frequency range of 125 to 4,000 hertz. Keep in mind, air traffic has a lower frequency while train/subway noise has a higher frequency. Products with high STC ratings may not be effective with specific frequencies.

In addition to STC ratings, the process of selecting sound-dampening products should also include measurements for transmission loss (TL) and outdoor-indoor transmission class (OITC).

Effective use of acoustic windows has become essential to keeping urban noise out and creating quiet interior spaces. So when your design calls for specific acoustic attenuation — be it hospitality, education, medical, residential, or other — our experts can help you find the best window for your acoustic needs – request a quote today or contacts us for more information.