One of the strongest and most efficient construction designs is the dome1. Dome structures like the Pantheon in Rome have survived for centuries, while other buildings around them have crumbled2. Modern architecture has avoided the dome, but it is making a comeback thanks in part to production techniques developed here in the United States. VOA's Greg Flakus has more in this report from Vermillion, South Dakota.
Wood-frame homes with standard roofs are the norm in this Midwestern college town, but there is an odd new addition here. On a tree-lined street only a few blocks from the University of South Dakota campus there is a three-dome home made mostly of concrete.
It was built by Kevin Meylor.
"Some people really like it, and some people don't," said Kevin Meylor. "That is a personal preference. Beauty is in the eye of the beholder3."
Meylor says the beauty of this house is that it is impervious4 to termites5 and other common problems faced by wood-framed structures, which he says are basically made of sticks. He says the aerodynamic dome is also safe from tornadoes6 that often hit this part of the country.
"A regular stick house, and this happens in hurricanes, too, if you get a little break at the corner it has a tendency to open up and blow the roof off," he said. "With this, it cannot happen because it is round and the air is going to go around it."
Another reason Kevin Meylor chose to build a domed7 structure is energy efficiency. This is a monolithic8 dome design, in that the basic dome structure is all of one piece. Such houses use anywhere from 50 to 75 percent less energy for heating and cooling than similar sized traditional houses.
Meylor obtained training and design assistance at the Monolithic Dome Institute in Italy, Texas, south of Dallas, where a number of domed buildings and residences can be seen from the interstate highway. One of the more intriguing9 is a long structure made of several domes10 in a row that has been painted to look like a huge caterpillar11.
Monolithic president David house is simple. A round-shaped fabric12 tent is inflated13 to provide the basic shape. Workers then spray the inside with polyurethane, which hardens the shell and also provides insulation14. The crew then attaches rebar, or steel bars, which provide more structural15 integrity, and finally, they spray over that with a special cement mixture.
"The mass of the concrete on the inside of the insulation is a huge factor in the heating and cooling," he said.
South concedes that most people in the United States are still not ready to live in domed homes, even though they can be as aesthetically16 pleasing as traditional ones. He finds that many women, in particular, do not like the outside look of a dome home. Monolithic domes have proven more popular for churches, gymnasiums, sports arenas17 and storage facilities.
But every year, hundreds of people from around the world come here to learn how to build a dome house at classes offered by the Monolithic Dome Institute.
David South says these simple, strong structures are especially popular in developing nations. He says an upcoming class will include visitors from Congo, who are particularly interested in small domed houses for rural villages.
"We are going to build one of the little eco-shell structures by hand to teach the people from Congo how to go back and do that same thing in their homeland," said South.
South has also been involved in large projects for homes and offices in India, where these structures have become quite popular.
Meanwhile, Kevin Meylor continues putting the finishing touches on his trinity dome project, which now draws many curious visitors. Dome enthusiasts18 like Meylor are providing people here in the United States with a new look at an old design and perhaps paving the way for dome-filled neighborhoods in the future.
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