The cooling effects of path designs in high-rise residential complexes: a micrometeorological study

Urban overheating and Urban heat island phenomenon negatively affect human health, and consequently increase energy consumption, imposing diverse environmental challenges. Many studies have reported that some treatments on the sidewalks -- such as using high-albedo pavements or changing street tree arrangements improves pedestrian comfort significantly and effortless. However, little is known about the extent of the cooling effects from the path to adjacent spaces in a block. This study focuses on assessing such effects in residential complexes in Suwon city, South Korea. Those residential complexes are ubiquitous in Korea, United States and China as contemporary residential development projects. They are a kind of modified version of tower in a park style complexes, usually consist of high-rise buildings and surrounding open spaces in generally 50,000 m2. The paths are laid out throughout the territory. We sampled two of those, first is flat plate building arrangement with 9 to 15 floors and second is tower-like building design with 15 to 32 floors. In order to assess the mitigation techniques in terms of the surface treatment and planting design, ENVI-met simulations were conducted for the two prototypical residential complexes. The main techniques adopted here are cool pavements and changing the arrangement of trees. Total 10 scenarios are made with combinations of the two items 1) increasing the Albedo and changing the material of the pavement 2) using equal-interval or clustered street planting. We simulated the ambient (Ta), surface (Ts) and physiological equivalent temperature (PET) for measuring microclimate and human comforts in 2 different time periods. The findings of this research will provide stakeholders with better guidelines for improving thermal comfort in outdoor workspaces in residential developments.