Study on external shading device dimensions of south-facing windows in Nanjing area

Taking south-facing windows in Nanjing area as research objects,and annual availability heat-gain from solar direct radiation as measurement index,three most commonly used external shading ways,i.e.horizontal shading,vertical shading and integration shading,have been studied.The results show that horizontal shading is recommended for south-facing windows in Nanjing area,the width of shading device should be 0.6~0.7 m,the distance between shading device and upside of windows should be 0.5 m and extended length at two ends should be 0.6~0.7 m by comprehensive consideration of different requirements for solar heat-gain in winter and sunshade in summer.Vertical shading and integration shading are not recommended because they don't have obvious shading effect.