A New York architect and green roof pro walks through the process of designing and installing a lush living rooftop The site: A more than 900-square-foot expanse atop a historic building in the Prospect Lefferts Gardens neighborhood of Brooklyn. The homeowner recently re-roofed the building, in anticipation of installing a green space, she had the roofer raise the skylights several inches and bring the waterproofing material up the sides of the roof?s walls.
The plan: The homeowner envisioned a wide carpet of greenery in addition to a small space for growing some fruits and vegetables, as well as an area to hang out with friends. She hired architect and green roof pro Inger Staggs Yancey of Brooklyn Greenroof to bring her idea to life.
According to Yancey, installing a green roof is like putting together a complicated puzzle, and because of this, it's not something you should DIY. During the initial design discussions?for this site, there were a lot?Yancey brings on a structural engineer. "The first thing you want to do is to find out how much weight the roof can support, whether it?s a lot or a little. That will change the kinds of designs you can entertain."
The plants: The engineer?s assessment showed that the roof could hold 55 pounds per square foot?enough strength to support a full rooftop farm. "The average green roof needs a minimum of 2.5 to 3 inches of growing media," Yancey explains. "If you?re going to grow vegetables, you need ...