November 15, 2004

News From HQ

American Society of Landscape Architects
Issues RFQ for Green Roof Installation at HQ

At the Salt Lake City Annual Meeting, the ASLA Board of Trustees voted to approve installation of a green roof demonstration project on the headquarters building at 636 Eye St., NW, Washington, DC. The decision of the BOT was based on a report from the Society's Green Roof Task Force—a group convened in 2004 and charged with investigating and making recommendations on the feasibility of installing a green roof on the ASLA headquarters building.

A close-up of the ASLA roof (middle) at 636 Eye St.

ASLA is pleased to announce that as a result of the BOT action, the Society is now seeking a landscape architecture firm to provide lead design and project coordination services for design and installation of the green roof demonstration project on the ASLA headquarters building.

With the existing roof on the ASLA building nearing the end of its useful life and a replacement scheduled to be made within the next one to two years, researching the possibility of a green roof installation at headquarters was both appropriate and timely.

Landscape architects are familiar with the environmental benefits of green roofs. They improve air quality by filtering air and producing oxygen. In addition, green roofs reduce stormwater runoff—retaining 70 to 80 percent of precipitation in summer, for example. The ability of this technology to mitigate urban heat island effect is well-known in Europe and is beginning to be demonstrated in the United States. The green roof on Chicago's city hall stays as much as 40 degrees cooler in the summer than the roofs of the surrounding buildings.

ASLA and the profession at large are committed to environmentally conscious design, and replacing the conventional roof with an ecologically sound alternative was worth exploring. As a first step, the task force prepared an RFP for and assisted with the identification of a structural engineer to assess the roof's structural capacity. Robert Silman Associates, PLLC, was retained for the study. The Silman Associates' report indicates that the ASLA headquarters building can support a green roof. Specifically, the report indicates that the existing roof structure has "sufficient reserve capacity to accommodate between 50 and 75 pounds per square foot (psf) of additional dead load from the proposed green roof system." The engineering study also showed that the headquarters building can easily accommodate modifications to improve roof access.

This photo shows the ASLA headquarters from the roof of another building in the neighborhood. As you can see, there is not a lot of green showing.

In addition to reviewing the report of the structural engineer, the task force conducted preliminary research and discussed aspects of the green roof project, including purpose, type(s) of green roof systems that should be considered, roof access, selection of the lead landscape architect, and general project parameters.

The task force recommended that ASLA should proceed with the green roof project with the goal of installation by fall 2005. The BOT agreed that a green roof project is not only consistent with ASLA values but also will demonstrate that the Society and the profession are taking a leadership role in promoting environmentally conscious design. Through monitoring and research, the ASLA headquarters green roof will add to data showing the economic and environmental benefits of a green roof and will heighten the profession's visibility in an increasingly important area of practice.

"By putting a green roof on ASLA headquarters, the Society is putting its values into action," said ASLA President Patrick Miller, FASLA. "We are proud to support this ecological technology and to make a contribution to improving the urban environment of which the headquarters building is a part."

ASLA thanks the members of the Green Roof Task Force:

J. Kipp Shrack, FASLA, Chair
Dennis Carmichael, FASLA
Bruce Dvorak, ASLA
Jeff Lee, ASLA
Susan L. B. Jacobson, FASLA, Executive Committee Liaison
Patrick Miller, FASLA, Executive Committee Liaison

Download the Green Roof RFQ and supporting documents.