Design of a double-decked rooftop garden

Quick answer：

A double-decked rooftop garden design refers to the architectural planning and layout of a garden that is constructed on two levels on a rooftop. This type of garden is often found in urban settings where space is limited, and it serves both aesthetic and functional purposes. The design considerations include structural integrity, plant selection for climate and soil conditions, irrigation systems, and safety measures for accessing the upper deck. Roof gardens can improve air quality, provide insulation, and create a green space in urban environments.