GSD Green Roof Initiative

Partner: Katrin Scholz-Barth, Environmental Engineer, Washington DC

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Green roofs are on the rise in the US. 80% more green roofs were constructed in 2005 than in 2004. Although this statistic is very encouraging, green roofs still have a long way to go. Only 0.01% of all newly built and resurfaced roofs in the US are green. The ratio of green versus grey roofs is still miniscule compared to a country like Germany, where the rate is 7%, 700 times higher. This low overall US percentage is because the technology is a relatively recent import and still alien to the mainstream construction industry. Throughout Germany green roofs have been present for 20 to 30 years whereas in the US only for 5 to 7 years. The unfamiliarity of the technology makes green roofs more expensive than in Europe and builders tend to be reluctant to include them into their projects.

Under these circumstances, the GSD Green Roof Initiative was founded to study technologies that decrease overall installation costs. The intention is to promote widespread application of green roofs in the US by demonstrating that green roofs can be both ecological and economical.

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The GSD Green Roof Initiative sought to study a low cost application on a real building and chose the roof of the Harvard Graduate School of Design as its subject. Since 2006 several installations have taken place on the roof of the school; collectively the installations have resulted in the greening of about 40 percent of the total roof area. Approximately 5,000 square feet are covered with Sedum sp. cuttings in separate plots within which a variety of soil mixes are being tested. The use of cuttings harvested from other projects contributed to the green roof’s low cost, but perhaps more substantial savings were realized as a result of an in-depth pre-construction analysis of the hydrology, plant-soil dynamics, and the existing roof design, uses, and maintenance issues. Specifically, the current studio roof consists of gravel ballast on top of insulation and an EPDM rubber waterproof membrane. The existing roof membrane is made of a material that also performs as a root barrier. The simplicity of the pilot design thus emerged through the use of the existing gravel ballast as both the drainage course and the soil medium, thereby affecting cost savings in labor and materials.

If the GSD pilot program is successful, green roof cost estimates will decrease from approximately $4.00 - $10.00 per square foot to less than $2.00 per square foot. Developers and roofing contractors won’t be able to afford to not go green and the cumulative benefits from wide scale coverage of green roofs will significantly improve the health and experience of cities.

In the meantime, the GSD Green Roof serves as a living experiment used for research and teaching in the school and nationwide. Many green roof experts, prospective builders and student groups from Harvard and various other universities have already visited the roof.
Plant progress is closely monitored by the initiative. After one growing season the comparative success rates of different soil mixes can be already observed. A detailed technical report will be published following the third growing season (2009).

TransUrban
Charting the City of the Future

Partners: Thomas Schroepfer, Assistant Professor in Architecture, Graduate School of Design
Limin Hee, Assistant Professor in Urban Design, National University of Singapore

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The indiscriminate proliferation of the word “sustainable” has created a serious crisis for the concept of sustainability and the word itself. Today every major construction project claims to achieve some state of sustainability or be at least more sustainable than previous projects. In this new world of green conscience, the “S” word unfortunately has often been manifested as a dubious marketing tool, rather than a respectable fact. The crisis is heightened by the ambiguous definition of sustainability and the lack of clarity about which practices are in fact more sustainable than others. This insecurity often leads to the total negation of the term. Some theorists claim that sustainability is a phantom and in essence unattainable. Some philosophers say the “S” word is so popular because it soothes society into consumption with a good conscience. Most recent the “S” word has been dropped altogether and is replaced by the indefinite “G” word: green.

Inspired by this climate of uncertainty TransUrban was founded to investigate recently built cities that are considered to be at the forefront of “sustainability”. TransUrban seeks to examine built experiments that go beyond environmental and ecological aspects. These cases should embody complex topics of design, dwelling, community in space, building technologies, environmental strategies, as well as models of affordability, while exploring new trajectories in the development of the city. At best these topographies of change re-contour the forms of urbanism as we know it, and do not conform to generic typologies, but create in concert a shift of paradigms. The patterns that emerge reveal complexity and integrated thinking across disciplines. TransUrban charts this terrain to find applicable design strategies for the future.

The interdisciplinary composition of the TransUrban group aims to address the spectrum of design and planning disciplines - landscape architecture, architecture and urban design and planning- thus allowing the group to examine the built experiments in sustainable cities from many angles. The chosen cases fit a specific profile: each must be recently completed, must be a critical size (minimum of 3,000 inhabitants) and must be internationally acknowledged role models for sustainable city development. In the first phase of data collection TransUrban visits these sites several times and leads extensive discussions with stakeholders, planners, agencies and citizens. In the second phase TransUrban analyzes the accumulated data, compares the original guiding urbanism principles with the ultimate built product and identifies the particular strengths or weaknesses accordingly. In the third phase TransUrban draws conclusions, highlighting new parameters for the future development of similar experiments.

TransUrban’s first case study was the new city quarter Vauban: a 38-hectare former barracks site near the town center of Freiburg, Germany. The site was purchased by the city in 1994 with the goal of converting it into a flagship environmental and social project. Vauban comprises today 2,000 homes to house 5,000 people, as well as business units to provide about 500-600 jobs. The project is currently nearing completion and is widely seen as one of the most positive examples in Europe of environmental thinking in relation to urban design.

TransUrban’s investigative work on Vauban resulted in an exhibition that was shown in five cities in Asia and Europe and the publication of the book TransUrban. Charting Experiments for Cities of the Future. Case I: Vauban in the Design and Technology Series of the Graduate School of Design at Harvard University.

A second case study is currently underway. It reviews the recently completed ‘Solar City Linz, Pichling’ in Austria, a new city quarter with 3,000 inhabitants and a special focus on energy efficiency.

Dirty Work
Landscape in the Non-formal City

Partner: John Beardsley, Art Historian, Senior Lecturer, Graduate School of Design

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There are now approximately one billion people living in squatter communities worldwide, a number expected to double by 2030. Between 60 and 90 percent of urban growth takes place in slums. Every day over 150,000 people leave the countryside and the majority pours into non-formal and extra-legal settlements. Squatter settlements vary dramatically in size, character, and level of political and social organization; they are found both in rural and urban areas, although they are increasingly associated with the world’s largest cities, especially in Latin America, Africa, and Asia. These settlements typically have a host of problems: they occupy marginal lands in flood plains or on steep slopes; they are separated from urban landscape infrastructure, be it roads, transportation, sewers, water supply, or storm water systems; they have severe environmental, public health, and security problems; and they lack public space for economic, cultural, or recreational activities. In short, non-formal settlements might be the biggest universal challenge after global warming.

Dirty Work investigates landscape interventions in these communities. In recent years, prevailing strategies for addressing non-formal settlements have shifted from large-scale slum clearance and relocation to on-site upgrading and improvement, with the goal of integrating these communities within their larger urban contexts. Contemporary designers are attempting to upgrade these settlements physically without destroying them socially.  They aim to retain what they can of their physical structure while alleviating environmental and social problems ranging from inadequate housing to unemployment, insecure land tenure, and unsanitary conditions. The main focus is not on the upgrade of the individual dwelling, but on the public space in between them--clearly a landscape objective.

Dirty Work is studying the various modes of operation in these upgrading projects. They range from large scale infrastructure networks like new drainage and transportation systems to small scale interventions like the construction of a staircase or a playground. In all cases the active involvement of the community is key to the success of the built intervention. The social challenges often surpass the physical ones and require an artful negotiation process with the community and powers in force. The distinct differences between these planning conditions and issues of traditional design practice have led to the formation of new activist and entrepreneurial practices. In the absence of government programs many of these offices thus operate as their own client and are deeply involved in the messy procedures of community participatory design under constantly shifting circumstances.

In the context of the genealogy and typology of these design interventions Dirty Work is equally interested in their longevity and sustainability. It is not yet clear if upgrading can achieve significant permanent improvements or if it will merely perpetuate social and spatial inequalities, with large percentages of the population packed into disproportionately small areas and cut off from basic services. In addition to social uncertainties the handling of natural resources within some of the upgrading projects must also be questioned. For instance, in the effort to provide basic services sometimes outdated civil engineering solutions are applied: creeks are channeled into concrete culverts; shotgun concrete holds back slopes; wastewater is piped downstream. One questions whether more environmentally friendly technologies could be introduced. Since the environmental footprint of the average slum dweller is decisively smaller than that of anybody living in the Western world, an environmentally smart retrofit of squatter settlements might lead to a new appreciation of squatter settlements.

Dirty Work plans to exhibit a wide array of practices and upgrading strategies that have been explored in Central and South America in a Gund Hall Exhibition at the Graduate School of Design from January 28 to March 16, 2008. The exhibition will be followed by a lecture series in Spring 2008.