Green roofs are increasingly fashionable, but they're nothing new -- elaborate roof plantings were used in Rome and Mesopotamia 2,500 to 3,000 years ago. The best known were probably the Hanging Gardens of Babylon.
Simpler green roofs have also been used for millennia by Scandinavians and Kurds. Homes were made of mud; weeds grew on the mud and created sod that helped keep the home warm or cool.
Going green on your roof will improve visual and aesthetic impact, and can prolong the roof's life. It reduces heat loss in winter and heat gain in summer, and can reduce water runoff by as much as 50 percent while putting to good use an otherwise unused space, providing habitat for birds and butterflies. Using the rooftop expands living space for activities such as dining, recreation and enjoying city views.
The benefits of gardening on the roof are so many that the Environmental Protection Agency is encouraging cities to start roof garden programs. The EPA's goal is decreasing the heat-island effect found in cities, which raises temperatures in urban and suburban areas by several degrees. The agency estimates that increasing an urban area's acreage of planted space by just a few percentage points can lower temperatures several degrees, significantly reducing smog and saving millions of dollars in energy costs.
Some gardens at the J. Paul Getty Museum of Art in Los Angeles are green roofs, too. There's a lush garden on the roof of Chicago's City Hall. Green roofs dot the tops of offices and residences in New York, Philadelphia, Boston and San Francisco. In Washington, there are several buildings with such roofs, including the national headquarters of the American Society of Landscape Architects.
Going green on your roof will improve visual and aesthetic impact, and can prolong the roof's life. It reduces heat loss in winter and heat gain in summer, and can reduce water runoff by as much as 50 percent while putting to good use an otherwise unused space, providing habitat for birds and butterflies. Using the rooftop expands living space for activities such as dining, recreation and enjoying city views.
The benefits of gardening on the roof are so many that the Environmental Protection Agency is encouraging cities to start roof garden programs. The EPA's goal is decreasing the heat-island effect found in cities, which raises temperatures in urban and suburban areas by several degrees. The agency estimates that increasing an urban area's acreage of planted space by just a few percentage points can lower temperatures several degrees, significantly reducing smog and saving millions of dollars in energy costs.
Some gardens at the J. Paul Getty Museum of Art in Los Angeles are green roofs, too. There's a lush garden on the roof of Chicago's City Hall. Green roofs dot the tops of offices and residences in New York, Philadelphia, Boston and San Francisco. In Washington, there are several buildings with such roofs, including the national headquarters of the American Society of Landscape Architects.
