ARLINGTON -- When a tornado threatened his construction site on April 3, Kevin Drake knew just where to seek sanctuary: inside the unfinished home of Trinity United Methodist Church.
Turns out, the 75,000-square-foot building on West Green Oaks Boulevard near Pioneer Parkway was spared a direct hit, although the site was showered with debris from the twister that hit a nearby nursing home and neighborhood.
With a framework of insulating concrete forms, the church will offer refuge against not only worldly temptations but also howling winds -- able to withstand the equivalent of a 15-foot two-by-four hitting it at 100 mph, according to testing done by the Wind Science and Engineering Center at Texas Tech University.
"This is one of the safest sites in Arlington," said Drake, construction manager for Fort Worth-based FPI Builders. "I would think it would fare very well" in a tornado.
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Projects like Trinity's raise public awareness of tornado-resistant construction techniques and may lead to greater acceptance of them, said Ernst Kiesling, a professor of civil engineering at Texas Tech and executive director of the National Storm Shelter Association.
The 17 tornadoes that hit North Texas that afternoon caused hundred of millions of dollars in damage but took no lives. At the very least, Kiesling said, the outbreak should be a wake-up call for the need for more storm shelters, whether public buildings or reinforced rooms in a home, he said.
Government incentives, like mitigation grants from the Federal Emergency Management Agency, can also help, but funding is usually scarce.
Tarrant County, for example, received $400,000 in 2010 for homeowners to use on tornado safe rooms, and that money is long gone.
"My bottom line is that the [property owner] is the key person who decides what is going to go in," Kiesling said. "Waiting on the government to create incentives or adopt new standards is an unsure and complicated path that can take a long time.
"It's like wanting to win the lottery without buying a ticket."At Trinity, the new buildings are being constructed with insulating concrete forms, a technology that originated in Europe after World War II and has been slowly catching on in this part of the U.S., said Ann Crocker, the church building committee member who suggested the material.
"It's not an easy sell because it's different" and because consumers are still largely unfamiliar with it, said Crocker, a partner in Energy Smart Solutions, a two-person firm that promotes the concrete forms.
Rather than using the traditional structural steel and other materials, the church's exterior infrastructure is made of concrete blocks connected with rebar and sandwiched between layers of hardened foam that serve as thermal insulation.
Lower energy costs
The lightweight foam blocks, or planks, are energy-efficient and highly durable.
Not only is the material much more wind-resistant, but if installed with other elements like doors and windows to create an airtight envelope, it can reduce energy costs by 70 percent, Crocker said.
"It gives us a much sounder and energy-efficient building," Pastor Scott Youngblood said. "And the building will last much longer. It will be one of the safest buildings in Arlington."
The concrete forms turned out to be cheaper for Trinity than traditional construction materials like steel.
For a different project, depending on the cost of concrete and steel, they might cost more.
Ultimately, the decision on how much to spend on wind protection might take into account the relatively low likelihood of sustaining a direct hit from a tornado, experts say.
While building a 100 percent tornado-proof structure is probably possible, the cost might be "astronomical," said Raleigh Roussell, president and CEO of Texo, an association representing commercial contractors in North and East Texas.
"If I were building a new house, I'd put in a basement," he said. "It's not going to save all your property, but it will save lives."
Of course, a cheaper and quicker alternative would be to install an in-home shelter. Those can start at a few thousand dollars, although they're easier to install during original construction.
For some people, the extra money is worth the peace of mind.
"If you're at work and the kids are home from school, you know they have a safe place to go," Kiesling said.
Fort Worth is among the area cities that have adopted some newer international standards that address energy efficiency and structural soundness, said Jon Samson, executive vice president of the 150-member Greater Fort Worth Builders Association.
In the first phases of reconstruction, Arlington officials haven't noted a rise in construction practices tailored to prevent tornado damage, said Ed Dryden, the city's building official.
The city already requires that structures be able to withstand sustained winds of 76 mph and three-second gusts of 90 mph. Tornado shelters are designed to withstand 250-mph winds, he said.
Like Kiesling, Samson sees consumer education as crucial. In recent years, he said, builders have noted that customers are better-informed on structural issues and not just focused on square footage, amenities and price.
Just as important as proper materials, he said, is choosing a high-quality contractor.
"I would say that I would build a house with the best materials and the best contractor that I could find while striking a balance with cost-effectiveness and blending with the surrounding neighborhood," he said. "I would caution against overbuilding."
Patrick M. Walker,