Oklahoma is home to more Monolithic Dome schools than any other state in the nation. It will soon have one more as Dale Public School completes construction on a new steel-reinforced concrete dome facility that will serve as an events center and cafeteria. The 109-foot-diameter building is scheduled for completion in January 2012.
It was Oklahoma’s high risk of tornadoes that prompted several other school districts in the state to build Monolithic Domes, and Dale is no exception. The building, which meets the Federal Emergency Management Agency’s criteria for near-absolute protection from tornadoes, will double as a community disaster shelter.
“We needed a safe room for our community and we needed a new cafeteria for our kids, and the Monolithic Dome design allows us to combine the two,” said Charles Dickinson, superintendent of Dale, which is located about 30 miles east of Oklahoma City. “The rest of our buildings are metal, and our students have no place to go during tornadoes or other bad weather.”
Dickinson says the district’s 700 school children have had close calls from severe storms, and the new building will provide peace of mind.
“In Central Oklahoma, where we are located, we have dodged tornadoes right and left,” Dickinson said. “In May, 2010, a tornado touched down one mile south of our school, traveled two miles, wiped out 10 or 12 homes, and did tons of damage,” he said. “If that had touched down one mile north at 3 in the afternoon instead of 6 at night, it would have wiped out our entire school. Now we have a solution.”
Other Oklahoma school districts that have opted for Monolithic Dome construction in recent years include Dibble, Geronimo, Locus Grove, Buffalo, Hinton, Beggs, Okemah and Texoma. Dome schools can also be found in Arizona, Texas, Kansas, Missouri, Minnesota, Florida, and Idaho.
In these times of rising energy costs, the Monolithic Domes’ energy efficiency is becoming as big of a draw as their disaster resistance. “We have found that the energy savings over a period of 20 years will pay for the cost of the building,” says David B. South, president of the Monolithic Dome Institute (MDI) in Italy, Texas.
The buildings’ round design is one reason for their energy efficiency. Their spherical shapes cover the most amount of space with the least amount of materials. Because there is less surface area, not as much heat escapes in the winter or seeps in during the summer.
Since the domes are made of concrete, they have the added advantages associated with the concrete’s thermal mass. When the interior of the dome is heated or cooled, the concrete warms up or cools off, and then maintains that temperature for a long period of time. Consequently, the interior temperature stays relatively constant. When the insulation is placed on the exterior of the building, the dome becomes even more immune to temperature swings.
The construction method used to build Monolithic Domes is as unusual as the buildings themselves. The process begins with the placement of a ring beam footing and the pouring of a circular steel-reinforced concrete slab floor. In many cases, a stem wall is then erected to give the building straight walls and a more conventional look. Next, crews attach an Airform, a tarp made of tough, single-ply roofing material, which is inflated using giant fans.
Click here to see a video of the Dale inflation.
Once the Airform is inflated, work moves to the interior where treated wood is attached to frame the windows and doors. Three inches of polyurethane foam is then sprayed on the rest of the Airform, and a grid of steel rebar is attached to the foam. In the final step, crews spray on a layer of Shotcrete that ranges from 4 inches at the top to 8 inches at the base. The result is a permanent and virtually indestructible structure.
The new Monolithic Dome building in Dale was designed by Oklahoma-based architect Michael McCoy and is being constructed by Idaho-based South Industries.
Read an article in the Oklahoma City news website KOKO.com.