Application of Acoustic Testing in Fenestration

A growing interest in and awareness around acoustically rated fenestration products means that acoustic testing is increasingly critical to ensure end-user satisfaction with window, door, or wall systems.

What is acoustic testing?

Acoustic testing determines the effectiveness of a material to attenuate or absorb sound, reducing the levels of noise from neighbors, traffic, and other sources. In many cases, acoustic ratings are required to ensure customer satisfaction with noise insulation from increasing environmental noise pollution.

Subjecting fenestration products to Sound Transmission Class (STC), and Outdoor/Indoor Transmission Class (OITC) acoustic testing can help manufacturers bring a more acoustically efficient product to market and enable buildings to perform their function correctly. 

Sound transmission class testing case study

In a recent case study involving a double-hung window, our experts developed a solution to increase the Sound Transmission Class (STC) rating of the window and improve end-user satisfaction. In this study, the window had a target STC of 30 but was only testing to 25.

The STC and OITC ratings measure the ability of a building product to attenuate sound. They are defined as single number ratings that are calculated using values of sound transmission loss (TL), providing an estimate of the performance of a product.

Performing acoustic testing to meet window STC requirements

In the acoustic testing process, Element’s experts began by conducting initial testing to determine the problem. The first step was to measure the glass in use and determine if the combination of the glass and airspace was sufficient to meet the STC requirements. In this case study, the client was using a 3/4" overall IGU with a glazing makeup of 1/8" exterior lite - 1/2" airspace - 1/8" interior lite.

Testing results

It was determined that the glazing makeup might be sufficient to reach the targeted STC rating. First, a simple listening test was performed to protect against any leaks. Through further testing, the weather-stripping in the meeting rail was determined to be insufficient, allowing noise to penetrate the partition easily. Our experts recommended a different type of weather-strip and suggested that it may be necessary to increase the mass of the glass.

To learn more about fenestration acoustics testing, or how we perform sound absorption and sound transmission testing, please contact us today.