Sunday, July 02, 2006

Green Roofs

A green roof is a lightweight, engineered roofing system that encourages propagation of vegetation while protecting the integrity of the underlying roof structure. While the primary purpose of green roofs is to lower temperature, there are a range of benefits over traditional dark-coloured city rooftops. Vegetation lowers absorption and release of radiation and precipitation is trapped in foliage which increases local humidity and allows cooling via evapotranspiration. This decreases the energy used for cooling the building below

A green roof increases the longevity of the structure of the roof primarily by decreasing temperature variability and weathering, and lasts twice as long as a conventional roof covering. Rain water flow is regulated, decreasing storm water runoff and pollution into sewerage systems and the roof provides sound insulation to reduced noise. Other benefits include providing habitat for urban wildlife, reducing glare, increasing the aesthetic appeal (and hence value) of the building, and providing recreational space and educational resources.

Great examples can be found at the Solaire in Battery Park City, and its newly-opened sister building next door, the Verdesian. Both buildings are designed, built, and maintained in environmentally-friendly and sustainable ways. Waste disposal, water management, and energy systems decrease energy use, improve air quality, an reduce water pollution and waste.

More info. can be found here, here, here, here, and here.