Green Roof -- A Case Study: Michael Van Valkenburgh Associates' Design for the Headquarters of the American Society of Landscape Architects
Publisher: Princeton Architectural Press, 2007
Empty rooftops are the largest unused open space resource in the US; they take up to 30% of potential open space in densely urbanized areas. Recently there has been a strong movement in the US to use these roofs for more than just utilitarian equipment. Green roofs, well known in Europe, are now increasingly built in North America. They promise an array of benefits: longer roof life spans, better sound insulation, reduced indoor heating and cooling needs, and decreased storm water runoff. Vegetation on green roofs cuts down carbon dioxide and binds with dust particles, meanwhile cooling the roof surface and alleviating the "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 sound buildings.
There is currently a compendium of publications about green roofs that mostly stress the environmental benefits of the technology. The book Green Roof: A Case Study looks beyond the environmental towards the mental. The potential of green roofs to serve basic human needs is examined in a discussion of the new roof built upon the ASLA headquarters in Washington DC, designed by Michael Van Valkenburgh Associates. This roof combines features of traditional roof gardens (accessible and enjoyable) with typical attributes of green roofs (lightweight and low maintenance).
The "Green Roof Hybrid" is introduced as a model for the future city that argues the importance of social next to ecological elements in roof design.This model asserts that urban green infrastructure must progress from basic environmental problem solving to improving the mental and physical health of the urban dweller. This step is not necessary for moral reasons; it actually is important for the economic survival of whole regions. Mental health is the key factor for the long-term productivity of information based economies; accessible green roofs can contribute to that as a workplace amenity. They offer fantastic spaces of relaxation and contemplation thereby easing the stress of urban living and working. Regions with joyful green infrastructure will and already have the competitive advantage.