Curtains and drapes that can reduce noise pollution by more than half

Ben Cazzolato – benjamin.cazzolato@adelaide.edu.au

The University of Adelaide, Adelaide, SA, 5005, Australia

Cameron West
Acoustic Blinds and Curtains
Sydney, New South Wales, Australia

Tyler Schembri
The University of Adelaide
Forestville, South Australia, Australia

Peter Watkins
Acoustic Blinds and Curtains
Sydney, New South Wales, Australia

Will Robertson
The University of Adelaide
Forestville, South Australia, Australia

Popular version of 2pAA3 – Enhancing acoustic comfort with window coverings: Reducing sound transmission and reverberation times with a single product
Presented at the 185th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0023007

Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.

Noise pollution isn’t just a nuisance, it’s bad for your health. Prolonged noise exposure has been linked to several short and long-term health problems – both physiological and psychological. The World Health Organization has estimated an annual loss of “at least one million healthy years of life” due to traffic noise alone.

Traditionally curtains and drapes have been used for design and light control only. However, they also present a great opportunity for a comprehensive acoustic treatment. This is for a number of reasons:

1. They are installed over windows and glazing, which is where the sound commonly enters spaces;
2. Windows generally have a significant surface area and are typically very reflective, which presents an opportunity to remove noise via absorption when covered;
3. Unlike other acoustic treatments, they are a natural fit in most modern spaces allowing architects, designers and clients freedom in their design unconstrained by acoustics.

Extensive testing by qualified acoustic engineers in the Acoustic and Vibration Laboratories at the University of Adelaide, Australia have shown that it is possible to reduce noise pollution by more than half* with an acoustic interlining. The acoustic interlining is a mass layer that is sandwiched between two sound absorbing curtain fabrics. Together these layers block and absorb sound.

Figure 1: Measuring the sound transmission loss and sound absorption of an acoustic curtain in a reverberation chamber at the University of Adelaide.

The acoustic interlining was tested over four glazing conditions; open window, 4mm glass, 6.38mm glass and 10.38mm glass, across 15 different curtain configurations, totalling 76 tests. The plot below shows the reduction in sound pressure level in a receiving room when using a typical acoustic curtain as a room divider. In the plot we compare only using the interlining, using only the face fabrics, and the benefit of combining both face fabrics and interlining, with the latter providing a frequency-weighted improvement of 17dB. Similar results were obtained when the tests were repeated for the three thicknesses of glazing.

Figure 2: Reduction in sound pressure level (known as the level difference improvement) when using the acoustic curtains as a room divider.

We have generated two audio files demonstrating how these acoustic curtains reduce noise pollution: Room divider application using 1500gsm interlining, and 800gsm interlining over 4mm glazing applied to traffic noise.

Visit the Acoustic Blinds and Curtains website for more details on the curtain construction and informative videos demonstrating how these curtains reduce noise pollution and improve room acoustics.

Our testing has shown how curtains and drapes can reliably reduce noise pollution by more than half for both open and closed windows. This is a game-changer for architects and end-users looking for simple, cost effective noise reduction and sound absorption compared to other acoustic products and offer a functional alternative to traditional blinds and curtains.

*perceived noise reduction