An assessment of the effectiveness of acoustic treatments for balconies and open spaces as required by Queensland State Assessment and Referral Agency

This study examines the effectiveness of acoustic treatments required to fulfill “Queensland State Assessment and Referral Agency (SARA)” conditions for balconies or private open spaces in apartment units above the ground floor. SARA SDAP State Code 1 Performance and Acceptable Outcome PO42 mandates developers to use a combination of continuous, solid, gap-free structures or balustrades and highly acoustically absorbent material treatments for such locations. The study explores the relevance of SARA conditions to balconies and highlights the absence of specific statistical noise level criteria for upper-floor private open spaces affected by traffic noise from state-controlled roads in Queensland. Furthermore, the Code requires these measures for balconies “adjacent” to state-controlled roads, which DTMR defined to be within 100 m of a state transport corridor and/or infrastructure. To investigate these aspects, computational noise modeling was undertaken to predict and assess the impact of road traffic noise on balconies, considering factors such as diffraction, reflection, and direct noise propagation paths. The study also analyzes the potential benefits of acoustic treatments, which were found to be dependent on sight angles to and distances from state-controlled road. In certain cases, minimal acoustic benefits are observed. It is recommended that there is a shift from prescriptive acoustic requirements to performance-based and building-specific requirements within the SARA framework.