In addition to sunlight control, the physical structure of Brise Soleil systems can provide useful acoustic benefits. Many offices, schools and hospitals are located near roads and transport links and suffer from external noise. The acoustic benefits of Brise Soleil should be considered at the design stage.
How Louvre Geometry Breaks Up Sound
By their nature the angles of the individual fins of a louvre array will split or deflect incoming sound waves. Instead of the sound being focused down onto a single layer of glazing the sound will now strike a number of surfaces in a focus, thus allowing the sound to be ‘scattered’ – thereby reducing the intensity of the sound pressure at the facade.
The Air Gap as a Buffer
The air space between the Brise Soleil louvres and building facade creates an additional sound barrier, with sound dissipated in this secondary buffer. This secondary sound barrier enhances the total sound reduction of a façade where the glazing already contributes significantly to sound attenuation.
Blade Density and Spacing
As the density of the fins increases so too does the amount of interaction that sound can have with the surfaces of the fins. Thus for noisy environments such as those near a dual carriageway or a rail line, a higher density of fins may be required. For further information on the use of louvres for noise reduction see the Institute of Acoustics’ reference material on how sound behaves around building facades.
Pairing With Acoustic Glazing
Adding a Brise Soleil system to acoustic glazing increases the overall sound reduction. The Brise Soleil can act as a first layer of sound reduction and the glazing then be designed to provide additional sound reduction. There is more on Brise Soleil at Alu Systems.
Buildings That Gain Most
A small additional cost to improve the internal environment of a school on a busy road, a hospital ward next to a car park or an open plan office near a rail line is worth considering at the design stage.