The 1,400 square feet of sedum-dominated green roof was designed to complement the look and feel of the rest of the garden, improve the views of the structures from the high-rise buildings that surround the site, and contribute to rainwater capture and conservation efforts used throughout Citygarden. Both green roofs use tray systems, which are effective for water retention.
Green roofs have many benefits, particularly in urban settings. The cooling effect of the green roof helps reduce the "Urban Heat Island Effect," while decreasing the need for interior building insulation. A green roof will also produce cleaner air by filtering the air moving across it. Depending on the type of foliage planted, one square meter of green roof can remove up to 4.4 pounds of airborne particulates from the air every year.
Additionally, because they are protected from regular foot traffic, green roofs can become home to plants that are easily damaged by walking, and to birds that nest on the ground. The soil on these green roofs also becomes a safer habitat for insects.