Greening the Urban Rooftop
by
Nancy Kiefer - 
The rooftop at 10 G Street is about to get a lot greener—3,000 square feet to be exact. In real estate-scarce cities, commercial property owners nationwide are turning roof space into green space.
On this project, WRI and the property owner, the American Psychological Association, are soon to break ground (or roof) on its 8-story office building near Union Station in Washington, DC. Green roofs are a great idea in general, but what makes this one especially cool is the labyrinth at the center with its 7-circle design, like those found in some ground-level parks.
Architectural Drawing of the Green Roof: Source: American Psychological Association
Green roofs are advantageous not just for their aesthetics and the improvement they make to the urban landscape. Commercial property is a major energy consumer, and in the United States is responsible for 10 percent of greenhouse gas emissions. And considering the amount of time most people spend at work, environmental improvements to the workplace equate to better human health and well-being.
Before the Green Roof A rooftop garden will replace parts of this roof.
Here are a few green roof benefits:
- Green roofs are, in effect, a second roof. They reduce wear on the roof structure, extending its life by as much as 50 years. They improve insulation and reduce energy costs year-around. One study estimated that green roofs on all Chicago city buildings would save 720 megawatts annually (equal to several coal plants or one small nuclear plant) for a cost savings of $100 million.
- Green roofs also provide accoustic insulation, and can reduce noise pollution by as much as 50 decibels.
- Green roofs produce oxygen, absorb air pollutants and greenhouse gases, and reduce water loss due to run-off. 1,000 square feet of green roof provides enough oxygen for 110 people, and removes 41 pounds of airborne particles a year.
- Urban rooftops can reach 175 degrees fahrenheit in the summer. Green roofs can lower ambient air temperatures and reduce the heat island effect.
- Square footage is a valuable urban commodity. Green roofs reclaim space for personal use and relaxation, and provide habitats for wildlife.
- Green roofs can counteract “big box development” to make retail and commercial properties more valuable and attractive. In 2006, Wal-mart built a 67,000 square foot, self-irrigating green roof on top of one of its Chicago stores.
Green roofs are but one option that businesses are employing to green the workplace and urban environments. APA recently announced a 2½-year agreement with Pepco Energy Services to provide 100 percent green power to the building. And last year, WRI completed a LEED-CI Gold Certified 7,000 square foot buildout of its green office space to increase energy efficiency, reduce materials waste and improve its work environment.
The 10 G Street project is a partnership between APA and WRI, with funding and support from the TKF Foundation and the Chesapeake Bay Foundation. Contact me, Nancy Kiefer, for more information or to schedule a tour of WRI’s office space.