Building automation and urban soundscape

Background: The use of building automation technology is rising as it is often adopted by sustainable design principles, offering notable opportunities for improving aspects such as energy efficiency and human comfort (e.g., daylight, temperature, air quality). Rationale: The integration of mechanical equipment on building envelopes such as motorized sun-shading systems introduce a series of sounds, different from traditional sources in urban environments. Buildings with higher levels of automation and moving elements can be expected to become more prevalent with the increasing densification of cities and the progress of smart technologies. Methods: This study examines the effects of an automated shading system on the acoustic environment around a building, through a case study conducted in accordance with ISO 12913 guidelines for soundscape data collection and analysis. The methodology involves sound level measurements and binaural recordings to derive psychoacoustic indicators, as well as questionnaires to survey people’s perception on-site, and a laboratory experiment with virtual reality (VR). Results: The soundwalks and the laboratory experiment showed that when the shading system is moving, soundscape perception typically shifts toward chaotic and annoying. These effects were only worse in combination with other sources such as a nearby kindergarten. However, when the façade is still, and without kindergarten noise, the soundscape around the building is mainly perceived as pleasant, calm, and vibrant. The acoustic analysis revealed that the shading system can increase noise levels by up to 20 dBA over the background noise at 1 meter from the façade, with levels gradually blending the background at about 25 meters from the building. Conclusions: The results reveal that motorized shading systems in a context like this case study can significantly degrade the acoustic environment outdoors, raising sound levels beyond recommended safety thresholds, and negatively affecting people’s perception.