Roofing: Strategic Advantages of Green Roofs on Campus

By now, many American educational campuses have had their first green roof installed. The ability of a green roof to reduce high summer rooftop temperatures, absorb rain storm water and to improve the life cycle of the waterproof roofing itself has convinced institutions to accept a change to the sort of low-slope roofs that they had installed for decades. While most American facility administrators are becoming familiar with the basic issues regarding this emerging technology, there are a series of strategic advantages for educational institutions associated with green roofs that deserve some discussion.

Green Roofing adds valuable green space and is both functional and enjoyable.

Green Roofs
Conceal Parking For many educational institutions, the need for ample parking results in vast expanses of asphalt surface lots and concrete parking structures. While the cost of installing underground parking is significant, a ground-level green “roof” can add valuable green space that beautifies a campus. Instead of parking lots and ramps pockmarking the campus landscape, the greening of a campus through underground parking with lawns and gathering spaces on top provides a more picture-postcard campus experience that can be treasured by students and alumni alike.

At the University of Wisconsin-Madison Education Building, a surface parking lot lay between the facility and Lake Mendota, ruining the view. Even worse, a major campus pedestrian path also leads students to walk right through the parking lot to enter the building on the lake side. During a recent renovation and expansion, the parking area was lowered and covered with a green roof and plaza. The major campus path now crosses this landscaped plaza, and the Education Building appreciates a vista of Lake Mendota without an unsightly surface lot in view.

Green Roofs Become Valuable Recreational Open Spaces
As many American campuses continue to build out their remaining open space, they are finding themselves landlocked by neighborhoods with a shortage of high-quality outdoor, open campus spaces for students, staff and faculty. Green roofs on buildings offer an opportunity for new construction and recreational open space to co-exist.

Planning for Discovery World at Pier Wisconsin—a water resources education and science center on Milwaukee’s lakefront—was challenged with siting a 200,000 square foot facility in a politically sensitive location. A “tip of the iceberg” approach was the solution. Several large aquariums, water education facilities, a catering kitchen, loading docks and a 200-car garage were all placed underground. On the roof of the underground construction an open lawn was designed, which looks like part of the adjacent lakeside park. Today, families enjoy picnics, children play Frisbee, and students study on the broad expanse of green—never knowing they are on a green roof.

Green Roofs Ease Approvals
Building Discovery World on Lake Michigan was controversial and would not have occurred without deploying a green roof as a critical strategy to construct and conceal a large expanse of square footage and parking. The green roof allowed the project to receive the community support it needed to go ahead.

Similarly, the plan for Cambridge Commons, an off-campus, undergraduate residence hall for the University of Wisconsin- Milwaukee, initially encountered resistance from the Milwaukee River Work Group. The environmental group was opposed to having the hall built on the hilltop site overlooking  the Milwaukee River.  The solution was a LEED (Leadership in Energy and Environmental Design) Gold building on the former urban brownfield, with green roofs on the north and south wings. Native plantings on the roofs absorb rainfall that would otherwise run off into the river. The project’s highest roof also channels rainwater into an underground, 20,000-gallon storm-water tank, where stored water is slowly released to irrigate plantings around the building.

The key to community approval was a LEED building with green roofs; once the Milwaukee River Work Group enthusiastically endorsed the project, the city alderman voted for its construction.

Green Roofs Contribute to LEED Certification
If higher education campuses are sandwiched between the neighborhoods around them, frayed relationships can become contentious when a college or university needs to expand into an adjacent neighborhood. Successful institutions work with neighborhood groups to get their support and acceptance for new construction before zoning changes and political approvals are needed.

Because a large percentage of grassroots community organizations are highly interested in green buildings and LEEDcertified structures, they often object to traditional construction but are willing to support sustainable architecture. Green roofs can be a key element in such an approval process, as they are a visible symbol of a community or institution’s commitment to green design and development. They also contribute points to LEED certification.

Educational institutions across the country are, in fact, adopting LEED guidelines to demonstrate their commitment to sustainability. Green roofs contribute points related to mitigation of the “heat island” effect and storm water retention. The increased roofing insulation value that green roofs provide reduces energy usage, which adds more LEED points.

Green roofs were an integral part of the overall sustainable-design strategy that resulted in LEED Platinum certification for the renovated and expanded Education Building at the University of Wisconsin-Madison. Underground parking was concealed with plazas and green spaces, and a third floor roof over an atrium became a green roof with a deck for students and faculty to lunch and meet outdoors.

Green Roofs Help Restore Lost Natural Habitats
Additional LEED points are possible through innovation in increasing the biodiversity of roof gardens and plantings. Research into such possibilities is critical, because on most education campuses today, every last vestige of the native ecosystems that once stretched across a site—whether prairie or meadow, woods or wetland—have been replaced with buildings, parking lots and high-maintenance lawns.

Intensive green roofs on new buildings, with soil deep enough for carefully selected native species, offer the opportunity to restore at least a part of such lost flora. On-campus expertise provided by students and faculty from the biology or landscape architecture departments could result in a rooftop biodiversity showpiece unique to the campus.

Green Roofs: Environmental Education and Research Projects
Green roofs are a growing field of research and development, with new information on technological approaches to installing and sustaining diverse plant communities occurring annually. Colleges and universities could become part of this effort, partnering with industry to conduct in-depth research into technical assemblies, maintenance, plant materials and ecosystems appropriate to specific regions, temperature mitigation, storm runoff data, and many other areas pertaining to green roof development. An on-campus green roof project is an excellent forum for educating students in a developing technology and involving them in related research efforts.

The Zoological Society of Milwaukee’s Conservation Education Center has a roof covered with sedums. During heavy rainfall, the plants soak up excess runoff. Sensors embedded in the roof provide researchers with a data stream comparing the roof’s temperature with that of a conventional roof. Typical data from a hot summer day indicates the center’s roof is cooler than the traditional roof, and cooler than the ambient air temperature. As a case study, the center’s green roof provides an excellent example for other educational institutions.

Green Roofs: Zero Storm Water Discharge Zone
Storm water remains a significant problem for many campuses. Traditional roofs are impervious surfaces and shed all rainwater to grade or into storm sewers, where a rapid influx of water and debris can contribute to flooding and sewage discharge problems, which plague many communities. Green roofs hold rainwater in place, allowing it to be absorbed into the soil, used by plants and evaporated in the atmosphere over time. Green roofs can contribute substantially to storm water control on a campus.

The University of Wisconsin-Milwaukee campus is pursuing the goal of becoming a zero storm water discharge zone, using rain gardens, storm-water retention ponds and green roofs. The green roof on Cambridge Commons, for example, was designed to control storm water and improve the water quality of the river below the building. These initiatives also contributed to the project achieving LEED Gold certification.

Educational campuses are increasingly being asked to control the runoff their buildings and other impervious surfaces generate. Green roofs are a key component of transforming campuses into zero storm water discharge zones. At that point, the open space, LEED points, research and development opportunities, biodiversity and native habitat that green roofs also provide become an integral part of a comprehensive system for campus sustainability.

James Shields, FAIA, is a design principal in the Milwaukee office of HGA Architects and Engineers, and an Associate Professor of Architecture at the University of Wisconsin-Milwaukee.




Follow us:

Individual/Corporate Member: reports on the topics, issues, trends and products impacting
facility managers and similar titles in educational, health care and related industries across the United States.

 © 2016 FM Communications  •  About  •  Site Map  •  Copyright/Disclaimer  •  Privacy Policy  •  Web site design by EDJE Technologies