In creating a green roof for NYU Langone Medical Center’s Alumni Hall, HLZAE completely covered the existing roof with vegetation and a growing medium, planted over a waterproofing membrane. Additional layers include a root barrier and drainage and irrigation system. Green roofs serve several purposes for buildings including absorbing rainwater, providing insulation, creating a habitat for wildlife and decreasing stress by providing a more aesthetically pleasing landscape. Green roofs help to lower urban air temperatures and mitigate urban heat island effect.
Alumni Hall’s green roof retains over 7000 gallons of storm water. It also resolves chronic leaks in the auditorium spaces below and provides a pleasing garden for patients to look out onto.
The New York City Department of Environmental Protection offers a grant program for private property owners in combined sewer areas of New York City. The minimum requirement is to manage one inch of storm water runoff from the contributing impervious area. If selected, DEP will provide funds for the design and construction of the green infrastructure system. Eligible projects include blue roofs, rain gardens, green roofs, porous pavement and rainwater harvesting on private property in combined sewer areas.