Green roofs are a growing trend in both residential and commercial ecologically minded architecture. These types of roofs entail having a garden of sorts above your building instead of, or in addition to, on your grounds. A building with a green roof has vegetation on the roof, as in the example below, where a gardener tends an urban green roof.
Green Roofs for Healthy Cities tells us that
“a green roof system is an extension of the existing roof which involves a high-quality water proofing and root repellent system, a drainage system, filter cloth, a lightweight growing medium and plants.”
Because space is such a coveted commodity in many cities, finding new places to build mini-ecosystems is both logical and in my opinion, quite beautiful. Green roofs switch up the traditional hierarchy or strata of inhabited land, make more room for flora, and increase air quality.
The USA General Services Administration shares that some of the benefits of green roofs include: storm water management, energy preservation (and insulation), biodiversity and habitat expansion, a reduction in the urban heat islands effect (reducing the high levels of heat produced in urban areas with high levels of concrete and asphalt), increasing roof longevity, and, of course, aesthetics. It’s important when considering a green roof project that you understand native plant species, the buildings ability to uphold a roof and the water-proof water management necessities of such an undertaking. Green roofs are popping up in sophisticated architectural developments worldwide, and in 2015, the 4th International Green Roof Congress occurred in Istanbul, Turkey from April 20-21. If you are a fan of green roofs, this would have been a fun and educational weekend for you. This congress of the International Green Roof Association (IGRA) brought together 500 experts from 35 countries for lectures, workshops, and various other professional development and educational experiences. The motto of the congress was “Explore the Nature of Rooftops.”
The 2015 International Green Roof congress was held at the Zorlu Center (above) which has a series of green roof spaces that offer views of the Bosphorus Strait. This center embodies a wonderful juxtaposition and cooperation between modern architecture and organic life. A speech by Roland Appl, President of the IGRA, kicked off the conference and the first day was then comprised of lectures and award ceremonies. IGRA shares that
“The discussion flowed through the fields of engineering and design, eco-master planning and urban infrastructure, investor interest, and technical precision.”
Throughout the congress, prizes were awarded for trendsetting architecture, municipal green roofs, and to green roof pioneers. Major prize recipients were Tim Flynn, of Tim Flynn Architects, and Udo Dagenbach, of Glasser and Dagenbach Landscape Architects, for designing the new United World College in Dilijan, Armenia (below)
The undulating, layered roofs of the United World College are both lovely and functional. Ömer Selçuk Baz, of Yalin Architects, was honored for The Troy Archaeological Museum, which is near Çanakkale, Turkey. The first day of the congress also included an optional tour of the Zorlu Center and a catered evening boat cruise on the Bosphorus. During the second day of the congress, several memorable projects were presented by designers. These included Laura Gatti and her Bosco Verticale (vertical forest) in Milan, Italy. This residential double tower green roof project (below) won the 2014 International High-Rise Award.
A second featured project of the congress was the Marina Bay Sands Hotel in Singapore. At this hotel, three high rises are bridged with the Sands SkyPark, creating one of the largest cantilevers on the earth. Also featured, the new United College in Dilijan, Armenia opened in 2014 and has numerous green facades and green roofs planted with local vegetation. It also offers visitors access to libraries, labs, theaters, and lecture spaces.
Wolfgang Ansel, director of the IGRA, also presented on the International Green Roof City Network, which endeavors to enable networking in the field of municipal green roof policies. This network was created by IGRA, the City of Portland (Environmental Services) and the International Federation of Landscape Architects (IFLA). The International Green Roof City Network has created a policy toolkit that covers related regulations, incentives, strategies and public relation activities. An additional theme of the congress was
“’Green roofs in Mediterranean and Dry Climates’” in which “participants learned how transferring the Oasis Principle can change the concrete deserts typical of urban rooftop locations into charming oases.”
The IGRA shares that there are several types of green roofs, including the extensive green roof, the semi-intensive green roof, and the intensive green roof. These green roofs are all defined by the types of plants they use, their height and weight, and their irrigation and maintenance requirements. As well as being naturally aesthetically pleasing, the green roofs offer
“improvement of the climatic environment as well as new natural habitats for flora and fauna.”
The IGRA’s services include networking, newsletters, and initiatives for national green roof associations, workshops, and conferences. IGRA reported that the 2015 congress was successful, unique, had “no equal,” and proved the strength of the growing green roof trend worldwide. Summaries of all the speeches are available on the Green Roof Congress site. A related IGRA event, the European Urban Green Infrastructure Conference, occurred in November of 2015 in Vienna, Austria, with a focus on ecosystem services in an urban context.
One of the most famous green roofs in the US is the one at the California Institute of Science, which features unique round window portals (below).
If you’re a green roofs fan, you can even check out and build a green roof in the DC area, with DC Greenworks (example below).
So keep your eye out for green roofs near you and other types of gardening-meets-building innovations, such as vertical gardening and farming. An example of Patrick Blanc’s vertical gardening is below, in his Costume National Aoyama Complex Wall project in Tokyo.