Thermal performance of green balconies of residential buildings: A Case Study in Wari, Dhaka

This study investigates the impact of green balconies on the thermal performance and indoor environmental quality of residential buildings in Dhaka, Bangladesh, which experiences a warm-humid climate year-round. Green balconies, incorporating vertical landscaping or potted plants are evaluated for their potential to reduce indoor temperatures, enhance thermal comfort, and contribute to energy savings. Field measurements were conducted in a high-rise residential building, with data collected on indoor temperatures, relative humidity, and solar radiation for both green and non-green balconies. Results show that green balconies can reduce indoor air temperatures by up to 6.5 °C, with an average reduction of 3.0°C in room temperature, compared to non-green balconies. The presence of greenery effectively mitigates heat gain, particularly through evapotranspiration and shading, improving thermal comfort and reducing reliance on mechanical cooling systems. Additionally, green balconies contribute to energy efficiency, with potential energy savings of up to 20%. The study further emphasizes the importance of optimal design, including the use of densely arranged potted plants, to maximize the cooling effect. This research highlights the effectiveness of green balconies as a passive cooling strategy for tropical climates, offering sustainable solutions for residential buildings by improving both environmental and occupant well-being.