![]() ![]() But when you have a huge façade, the prevailing winds create a high-velocity downdraft and the microclimate around the base of those buildings becomes practically impossible. ![]() “Many huge towers have cafés and restaurants on the ground floor. Things aren’t much better at ground level, Meir adds. “People end up using these very expensive balconies for storage.” This makes balconies on very high floors unusable, even dangerous, due to high winds. “In general, the higher you go, the lower the ambient air temperature and the higher the wind velocity.” “The taller the building, the more diverse microclimates the different floors are exposed to,” says Meir. ![]() Who wants thousands of passersby looking at them in their pajamas? Microclimate mayhem Meir says all that glass serves no practical purpose (except possibly boosting curtain sales). Residential high-rises, too, are often fully glazed. “A square meter of ‘smart’ glazed façade costs much more to produce than a square meter of opaque façade.” However, using this technique raises construction costs and – because of the building’s larger footprint - municipal taxes.Įlectrochromic glass, low-e (low emissivity) glass and advanced nano-coatings that let in light but not heat may consume more energy in their manufacture than they will save over the lifecycle of the building, Meir adds. Studies by his grad students found that a double-skin façade, with an insulating air cavity between two glass layers, minimizes cooling and heating demand. In his hall of shame is the 55-story Bank of America Tower in New York City, which won a LEED Platinum rating for “green” construction processes.īut because it is fully glazed, this skyscraper “consumes much more energy per square meter compared to other towers in Manhattan without such certification.” Photo by Beyond My Ken via Wikimedia Commons “With a glass façade, the heat exchange with the environment, inwards or outwards, is much faster and more problematic than when the façade is opaque and insulated.” Bank of America Tower, Manhattan. “And that means we need huge air conditioners to get all that heat out,” Meir says. The large number of people, electric equipment and lights per square meter in office towers adds more heat on top of the solar radiation pouring in on sunny days. “Anything past 100 meters is an environmental disaster - and even 100 is way too high.” “Using glass as an envelope material means we are building greenhouses, creating an unbearable environment for the people in those buildings.” “Most tall buildings are fully glazed with glass from floor zero and up,” says Meir. Let’s summarize the problems motivating Meir to send an anti-skyscraper message to his students and to urban planning professionals everywhere. “Even with today’s growing population density, we could easily limit buildings to no more than 15 stories.” ![]() “Anything past 100 meters is an environmental disaster - and even 100 is way too high,” Meir asserts. As of today, there are 115 supertalls and three megatalls completed globally, with more under construction. A “megatall” building tops 600 meters (1,968 feet). What defines tall?Īccording to the Council on Tall Buildings and Urban Habitat, a building of 14 or more stories – more than 50 meters (165 feet) high – may be classified as “tall.”Ī “supertall” building rises higher than 300 meters (984 feet). “A multidisciplinary team has been working with me on the issue of tall buildings for nearly 10 years and I don’t think we’ve gotten to half the issues yet.”Ī member of Ben-Gurion University of the Negev’s department of civil and environmental engineering and School of Sustainability and Climate Change, Meir will be the keynote speaker at the International Council for Research and Innovation in Buildings and Construction’s SBE23 Sustainable Built Environment conference in Greece this March. “I keep screaming bloody murder,” he tells ISRAEL21c. Isaac Meir looks at the towering glass-and-steel skyline, he sees an environmental, economic and social catastrophe. And they conserve space in increasingly dense urban areas.īut when Prof. Saudi Arabia is planning a skyscraper of more than 167 stories, stretching a kilometer (0.62 miles) into the clouds.Ī few reasons: Supertall buildings have an aura of success and sexiness. The half-mile high, 163-story Burj Khalifa in Dubai is the world’s tallest building… but not for long. ![]()
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