The benefits of green roofs are many: longer roof lifespan, greater sound insulation, reduced heating and cooling system needs, and a cutback in storm water runoff. Green roofs decrease carbon dioxide and increase oxygen in cities, making them cooler in the process and reversing the so-called "urban heat island effect." In short, green roofs are the great green hope of many environmentalists, politicians, and architects interested in more efficient and environmentally aware buildings. From a design standpoint, however, there is less consensus. While some see the roof garden as a visual statement using plants, geometric lines, and sculptural elements, others believe concerns for sustainability should outweigh visual appeal. A green roof that combines aesthetics and mechanics has become the goal of many a landscape architect.
To address this quandary, the American Society of Landscape Architects (ASLA) commissioned renowned landscape architects, Michael Van Valkenburgh Associates in collaboration with the Conservation Design Forum to design a 3,300-square-foot green roof garden for its Washington, D.C. headquarters. In Green Roofss, author Christian Werthmann uses this detailed case study to explain the history, methodology, and design process of green roof garden construction, providing a rich source of inspiration and technical knowledge for anybody interested in this simple solution to many of the environmental challenges we face today.
Christian Werthmann is an assistant professor of landscape architecture at Harvard University's Graduate School of Design. Before joining the GSD faculty, he was an associate at Peter Walker and Partners, working as project landscape architect on a series of major design projects including Clark Center at Stanford University with Foster and Partners, the new University of California State Campus of Merced with SOM and the San Jose Airport master plan with Gensler.
...a garden in the sky becomes fashionable, Nevada Appeal:
"An up-to-date how-to volume that shows that it is possible anywhere, with the proper planning, to install a rooftop garden."
"Generously illustrated entries span the A to Z of green-roof design and construction, including drainage, erosion, maintenance, and planting. "
— David Soltesz
Chicago Botanic Garden:
"Meeting contemporary environmental challenges in urban centers, the concept of the green roof - the terminology for growing vegetation on the top of a building - is the focus of this discussion by landscape architect Christian Werthmann. "
— Marilyn K. Alaimo
"Green roofs are the great green hope for advocates of more efficent and environmentally aware buildings. As the first to achieve the difficult balance between sustainability and aesthetics, Michael Van Valkenburgh Associates new green roof garden for ASLA headquarters in Washington, D.C. makes an ideal case study for architecture students and professionals."
Up high and down to earth, Boston Sunday Globe:
"Green roofs are a hot item in architecture. Mayor Menio, for one, advocates them for all new buildings in Boston."
"The rarest of architectural books...successfully balances theoretical concerns...After years of blah rendering-filled monographs and cheeky formal explorations, this kind of book is not only welcome, but long overdue."
Grow Up, Sunday Daily News:
"Greening your roof requires study and planning. Structural integrity, grading, waterproofing, drainage, growth mediums and plants are important."
"This book has excellent graphics and color photographs. It is an up-to-date how-to volume that shows that it is possible anywhere, with the proper planning, to install a rooftop garden."
Skys the limit if you grow a green roof, The Recorder:
"Going green on your roof can prolong its life. It reduces heat loss in winter and heat gain in summer, and can reduce water runoff by as much as 50 percent."
Up High and down to earth, Sunday Telegram:
"A superb book about the ASLA roof Green Roof: A Case Study has been published by the Princeton Architectural Press."
— Robert Campbell
"...readers are taken through each step of installing the green roof at the landscape architect's building. Every step of the installation for the rooftop and terrace gardens is clearly explained. This book has excellent graphics and color photographs. It is an up-to-date how-to volume that shows that it is possible anywhere, with the proper planning, to install a rooftop garden."
BBC Gardens Illustrated :
"follows the creative process as Michael Van Valkenburgh designs a new headquarters for the American Society of Landscape Architects (ASLA) in Washington DC. "
"Green Roof is the seminal work, thus far, on green roofs...In a day when "green" is the buzzword of the building industry it behooves us to remove ourselves from the fad and engage in critical conversation regarding the potential of the green roof and where it can take us. We owe both Valkenburgh and Werthmann a big thank you for beginning the conversation. "
Turning a roof into a garden in the sky, Mail Tribune :
"Readers are taken through each step of installing the green roof at the landscape architects building. Every step of the instalation for the rooftop and terrace gardens is clearly explained. This book has excellent graphics and color photographs."
— Joel M. Lerner
Lofty Location, Reporter - Herald:
"Going green on your roof will improve visual impact, and can prolong the roofs life. It reduces heat loss in winter and hat gain in summer, and can reduce water runoff by as much as 50 percent while putting to good use an otherwise unused space, providing habitat for birds and buterflies."
— Joel M. Lerner, APLD