The third little pig has nothing on Phil and Maxine McDonald.
Brick? The McDonalds are going whole hog for safety–and energy efficiency–with full concrete construction in their new home, under construction just west of Mustang, Okla.
They saw the process explained at a home and garden show several years ago. They went to some seminars on concrete construction and were particularly drawn by the prospect of energy savings.
“The more we heard, the more impressed we were. We just think it’s much better,” Maxine McDonald said.
Then came the May 3, 1999, tornado, which clinched their decision.
“If we had any doubt, that cleared it up,” she said.
Almost with the first thunderclap of storm season–the atmospheric cacophony that announces a churning sky and fury of an Oklahoma thunderstorm–David Tosh’s phone will start to ring in Oklahoma City.
Business at Insulating Concrete Homes, which Tosh co-owns with Mike Garrett, will be swirling like the debris cloud surrounding a twister.
“Usually the first sign of a storm” brings the year’s first flurry of interest in the company’s concrete homes and safe rooms, Tosh said. “When the weather starts up, we start getting calls. By March-April-May, we’re going wild on storm shelters.”
And concrete homes. Tosh said the company builds between 40 and 50 homes a year, mostly custom models from plans by Oklahoma City designer Charles Custer, using insulating concrete forms .
In addition to the concrete walls, the company’s homes usually have a safe room, an especially storm-resistant space, like the 4-by-6-foot shelter in the McDonald home.
Concrete homes cost about 10 percent more than traditional homes, said Stan Malaske of SWM & Sons Homes, which is building its first house with the Insulating Concrete Homes system.
Tosh estimated that the process is used in 1 percent or less of homes being built around Oklahoma City, but the number is growing. Nationally, Tosh said, concrete construction is being used in 2 to 3 percent of new homes.
The process isn’t complicated. It boils down to “stack, brace and pour,” he said.
Hollow foam blocks and panels are stacked in the shape of a building, then filled with steel-reinforced concrete. The forms are left in place after the concrete hardens, with the polystyrene forms serving as insulation and the concrete functioning as the structure.
Tosh said the process and materials make for a home that is especially fire resistant and–of greater interest to many Oklahomans–storm resistant.
Concrete homes are 10 times as strong as traditional wood-frame construction, with walls that can withstand wind speeds up to 250 mph, Tosh said. The walls are 11 inches from inside surface to outside surface, with a 6-inch concrete core.
The Wind Engineering Research Center at Texas Tech University also found concrete walls to be far superior in resisting damage from wind-driven projectiles, he said.
Malaske is building a home for an engineer who also wanted a geothermal heating and cooling system, which added even more to the construction costs.
But the extra expense, Tosh said, will pay for itself.
Concrete homes, Tosh said, provide between 50 percent and 80 percent savings on heating and cooling expenses, compared to standard construction using R-19 insulation. Concrete walls perform like a wood- frame wall constructed for R-50 insulation, he said.
“It’s not much of what we do. It’s a good system. It’s an excellent system,” Malaske said.
“There’s some interest, but there hasn’t been a lot of them built in high-visibility areas,” he said. “I think you’re going to see more of them in the future.”
