Urban Agriculture: Green rooftops help make our cities more resilient, and even present innovative ways to grow food.

The weather during the 18-month data collection period July 2005 to January 2007 recorded 55.4 inches of cumulative rainfall, which was around average for Seattle. Noise Reduction: According to LivingRoofs, green roofs with a 12 cm substrate layer can reduce sound by 40dB and one of 20 cm by 46-50dB, but the level of noise reduction is dependent on the depth of the overall system. The test plot planting media they used were sedums and sempervivums. The engineers also found that the drainage layer was very important, and that while cellular drainage mats are often used, aggregate drainage layers can perform better and may be cheaper. For Seattle’s wet climate, they found that four to six inches was the best thickness for the vegetation. But even in the wet climate of Seattle, the roofs were able to rebound between events and absorb the rainfall. Therefore, every gallon of rainfall eliminated at the building site by a green roof is a gallon that does not require treatment with chemicals, processing, etc.”ĭespite absorbing so much rain run-off, the green roofs were not able to reduce it enough to eliminate the need for detention tanks. cities), much of this system is a combined sewer, which sends rainfall combined with sewage to wastewater treatment plants. described the environmental advantages of reducing the volume of run-off in combined sewer systems: “Every inch of rain (or gallon of runoff) eliminated by a green roof is runoff that does not enter the municipal storm drainage collection system. In an interview in the company’s newsletter, Drew A. The results showed that the green roofs reduced the rainfall runoff by between 65% to 94% - much more than had been modeled. The final report by Magnusson Kelmencic Associates is the result of over 1.5 million measurements of data gathered from five green roof test plots around Seattle’s downtown area. The home includes a single-story guest wing and garage, each featuring a living roof planted with wildflowers and local grasses by design firm Goode Green.Engineers in Seattle have completed an 18-month evaluation of green roofs to see how well they actually perform. Watermill Residence, Water Mill, New YorkArchitect Andrew Berman conceived this waterfront residence on Long Island as a summer and weekend retreat for three generations of one family. Click through these spectacular examples from San Francisco to Singapore to discover how top architects-including Pritzker Prize winner Renzo Piano and AD Innovator Weiss/Manfredi-are incorporating green roofs into their projects.

Factor in lower heating and cooling costs, extended roof life, and tax incentives (depending on the city), and it’s easy to see why this building trend continues to grow.

The sky-high functional gardens also have a wide variety of ecological benefits, such as the ability to absorb carbon dioxide, reduce stormwater runoff, limit heat absorption, and provide habitats for insects, birds, and other wildlife. Made with hardy varieties of succulents, grasses, wildflowers, and herbs atop several structural layers-including a waterproof membrane and levels for drainage, insulation, and filtering-these self-sustaining living architectural features can bring natural beauty to urban buildings or connect rural structures to their surrounding landscapes. Green roofs are sprouting up more and more on buildings around the world, from private residences and schools to cultural institutions and businesses.

Green roofs seattle