External sun shading devices are increasingly used in sustainable buildings to reduce the greenhouse effect in the summer, allowing significant energy savings. Another benefit is the reduction of the glare effect due to direct solar irradiation through transparent surfaces. The acoustic effects of these devices have not been well investigated in the literature, although recent studies show that their use can be optimized to influence acoustic comfort, even with open windows, but it can also lead to critical issues from the point of view of daylighting, especially with overcast skies. In the paper, the results of acoustics and daylighting simulations are reported, considering different dimensions, distances of the louvers and orientations of the façade. In previous works by the authors, the acoustic effect of shading devices was firstly evaluated in their usual material and then an improvement of acoustic properties was attempted: the bottom side of each louver was considered as a sound absorbing surface. Acoustic effects were evaluated in terms of Insertion Loss (sound pressure level differences between situations without and with shading system): effects of size, spacing and tilt angle of louvers were evaluated together with the height from the soil of the studied façade portion. Having defined a certain relationship between the distance of the louvers and their width, it is possible to observe how the absorption and sound insulation change as the size changes. For the lighting simulations, an average spacing and width of the louvers was examined and the variation of the shielding effect was studied referring to the inclination of the louvers and the orientation of the facade (West, South, East) for a specific latitude in the South of Europe.
The acoustic and daylight effects of external façade sun shading systems
Secchi S.;Fausti P.;Santoni A.;Zuccherini Martello N.
2021
Abstract
External sun shading devices are increasingly used in sustainable buildings to reduce the greenhouse effect in the summer, allowing significant energy savings. Another benefit is the reduction of the glare effect due to direct solar irradiation through transparent surfaces. The acoustic effects of these devices have not been well investigated in the literature, although recent studies show that their use can be optimized to influence acoustic comfort, even with open windows, but it can also lead to critical issues from the point of view of daylighting, especially with overcast skies. In the paper, the results of acoustics and daylighting simulations are reported, considering different dimensions, distances of the louvers and orientations of the façade. In previous works by the authors, the acoustic effect of shading devices was firstly evaluated in their usual material and then an improvement of acoustic properties was attempted: the bottom side of each louver was considered as a sound absorbing surface. Acoustic effects were evaluated in terms of Insertion Loss (sound pressure level differences between situations without and with shading system): effects of size, spacing and tilt angle of louvers were evaluated together with the height from the soil of the studied façade portion. Having defined a certain relationship between the distance of the louvers and their width, it is possible to observe how the absorption and sound insulation change as the size changes. For the lighting simulations, an average spacing and width of the louvers was examined and the variation of the shielding effect was studied referring to the inclination of the louvers and the orientation of the facade (West, South, East) for a specific latitude in the South of Europe.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.