Green roofs offer a lot of environmental benefits - they provide additional insulation, reduce rainwater runoff, and can lower your electricity bill. However a new study suggests that roofs painted white might actually be more effective at fighting climate change. A study published in the Energy and Buildings Journal compared three types of roofs - green, black and white - and came to the conclusion that white roofs have great economic benefits, and they are also three times more effective than the other two at fighting climate change. Researchers at the Lawrence Berkeley National Laboratory conducted an economic analysis of the costs and benefits of white, black and green roofs and found that white roofs are far superior in fighting climate change than the other two. While roofs painted black absorb heat and contribute to the urban heat island effect, white roofs reflect the sunlight back into the atmosphere and help cool down its lower parts. The study advises those concerned with global climate change to choose white roofs, adding to a host of other studies in the past decade that have allowed the "white roof movement" to gain momentum across the United States. However, things are not as simple as they seem. A series of climate simulations carried out by Mark Z. Jacobson and Ten Hoeve of Stanford University showed some unexpected results. Despite their beneficial effects on the lower parts of the atmosphere, white roofs decrease the temperature difference half a mile above ground-a difference which drives cloud formation and less clouds means more sunlight reaching the Earth's surface. This, among other issues like the impact on fossil fuel consumption and summer cooling vs. winter heating gains, is still subject of scientific debates. Meanwhile, it should also be noted that vegetated roofs offer built-in storm water management mechanisms in addition to some cooling benefits. Although we are excited to find out how different roofing strategies may affect climate change, one should be aware of the fact that these investigations involve a wide spectrum of factors and potential consequences far too complex for a hotheaded (pun intended) thumbs-up verdict. Earlier in 2012 Columbia University and City University of New York has found ; that greening NYC rooftops or adding a few coats of white paint can reduce temperatures by as much as 84%.

Authorities in Shenzhen, Guangdong province, recently discovered an illegal structure on the roof of a luxury high-rise, China Daily reported. The temple like structure was built on the roof of a 19-story residential building in the city's Nanshan district years ago. A thick metal door with a fingerprint lock separates the 19-th story from the roof. Liu Minxing, deputy head of the law enforcement team of the Shahe sub district office, said that after receiving the report of the illegal structure, his team went to the building several times, but couldn't check out the rooftop structure because they could not gain access to it. The structure's owner refused to open the door and did not meet the team, Liu said. But Liu said that the on roof structure is illegal because the law bans such structures from being built on roofs. Some people in the building said that the owner of the structure often held sacrifices in it, and ash of burned paper fell to the windows of their apartments. The owner of the rooftop structure is the owner of the apartments on the 19 floor, but the residential management office declined to provide any information about the owner, citing privacy concerns. According to a broker with a real estate agency nearby, the price of the building's apartments averages US$ 4,900 per square meter, and the total price of the 19 floor apartments was over US$ 2.5 million. "The owner of the apartments on the 19 floor who built the rooftop structure must be rich or a high-ranking official who had a lot of connections to avoid punishment," the broker said. Liu said his team will continue their investigation into the structure and try to get information about the owner from the residential management office. "If the owner refuses to co-operate with our investigation, we will connect with police, firefighters and the local safety supervision department to form a working group and find a way to open the door," Liu said. The owner could be punished under the law concerned if the structure is deemed to be illegal, Liu said. Earlier a Chinese man is believed to have illegally built an astonishing rooftop palace on the top of a residential building in Beijing . The bizarre two-story edifice - which looks like it has been carved from a mountainside - was constructed by a man known only as Professor Zhang on the top of a suburban apartment block. The professor is said to have spent over six years building his home, after knocking down the penthouse he bought on the 26th floor in 2007.

Google has been cleaning up existing buildings in cities across the globe, from San Francisco to Berlin, turning them into colorful work and play environments that are the envy of every cubicle worker. But now the company has unveiled plans to build a structure anew as an extension to their current headquarters in Mountain View, California. The corporate giant gave Vanity Fair the scoop on the green-roofed expansion, which was conceived in collaboration with Seattle-based design firm NBBJ. The 102 thousand square meter extension to the existing Googleplex in California will be constructed on an adjacent 170 thousand square meters site and will featured nine bent rectangles linked by bridges and a host of verdant courtyards and pathways. The buildings will be up to four storeys high and will be organized in accordance with employee work patterns. In other words, departments that work well together will be near each other, and there will be the usual communal and social spaces that encourage cooperation and creativity. One bridge will lead to a green roof and outdoor cafe and the entire complex will be heated with radiant flooring. This less energy intensive system will be the largest of its kind in the United States.

The benefits of white and green roofs are nothing new to us, but a recent study by two top NYC universities has shed light on just how effective these non-traditional roofs can be at lowering building temperatures. Non-reflective dark roofs are known to exacerbate the urban heat island effect and do absolutely nothing to reduce storm water runoff, which is why New York City sewers overflow almost every time it rains. But a recent study released by Columbia University and City University of New York has found that greening NYC rooftops or adding a few coats of white paint can reduce temperatures by as much as 84%! Just think how much that could help you out on your electricity bill this summer. In order to ascertain the real benefits of greening or whitewashing city rooftops, researchers studied three different roof surface treatments at the Con Edison Learning Center in Queens: a green roof, a dark roof and a white roof. Measurements on each one showed that on average the white roof was about 30 degrees Fahrenheit (17dg?) cooler than the dark roof, while the planted sedum roof was a whopping 60 degrees(33dg?) cooler! NYC is working towards applying white paint to one million square feet of rooftop a year in order to reduce those draining summertime highs, but city dwellers can do their part by taking the initiative as well. Green roofs, which cost about US$ 160 per square meter according to the New York Times, are even better. Not only do they reduce temperatures, but they also promote better air quality by absorbing carbon emissions and capture storm water runoff. Furthermore, depending on the size of each individual roof and personal budgets, it's possible to grow your own produce sans all the nasty chemicals and fertilizers that are coming under increasing scrutiny.