As I write this Letter from the Director, a new threat from Mother Nature is barreling up the East coast of the United States.  We are also about to observe the 10^th anniversary of the 9-11 attacks.  This letter, however, isn’t about hurricanes, tornadoes, climate change or terrorist attacks but rather about Man’s response to the threats we face and experience every day from Mother Nature and our fellow men.

Risk is a fact of life.  If you walk across the street or sit behind the wheel of a car you are taking a risk.  The chances that something life-threatening will happen are slim, but they are there.  You either take the risk or you stay inside your entire life (there are risks there also).   People, companies, all of us evaluate risk, at least subconsciously, every day.  You do what you feel is prudent and economically viable to minimize the risk, then you move forward.  The more you spend and the more cautious you are, the more you can reduce the risk but at some point it is simply impractical or even impossible to eliminate that additional element of risk.

The design and construction of our buildings also involve decisions related to risk.  All buildings are designed to keep their occupants safe from Mother Nature – to a point.  That “point” is typically determined by building codes, which set minimum standards for design loads.  Those loads vary depending on where the building or structure is located, the building use, and requirements of the owner.  For example, buildings in hurricane or earthquake prone areas are designed under different wind load criteria than buildings in Iowa or Nebraska because of the likelihood that structures in those areas will be subjected to more severe loading conditions.  Critical services buildings such as communications or public safety structures are often designed to withstand greater forces than a retail structure because of their need for continuous operation in an emergency.  Any buildings can be designed to withstand just about any force, but designing structures to withstand exceedingly rare events can increase the cost dramatically.

This brings us to Joplin, Missouri and the devastating F-5 tornado.  Many people lost their lives in this event and it was a tragedy that several were killed when they tried to escape the tornado in a building.  Unfortunately for our industry, the building happened to be a Tilt-Up structure.  Few, if any, of the buildings in Joplin (including the structure in question) or elsewhere in the US are designed to withstand a direct hit from an F-5 tornado.

Design for extreme events is an issue not just for Tilt-Up but the entire building industry.  TCA assembled a panel shortly after the Joplin event to evaluate the performance of Tilt-Up and other building systems to see if steps could be taken to reduce this type of disaster in the future.   The odds of that happening are extremely small and the cost of eliminating that risk in the average retail structure with modified building design and construction would significantly change the economics of our retail economy.

That doesn’t mean we should ignore the problem.  Is there a middle ground?  Is there some way that we can improve life-safety without adding tremendously to the cost of our buildings (which would be passed on to the consumer)?  Buildings can be strengthened, designs can be changed, but large box structures present some unique challenges.  Designing all buildings to withstand an F-5 tornado is probably not a realistic alternative.  Another option might be safe rooms designed for high wind or other natural disasters just inside the entrance to structures that otherwise are not designed to withstand this type of force.  This is already happening in many residential structures.  A safe room could serve the store occupants as well as the general public and would not have to add significantly to the cost of the structure.  It could also be a retrofit to existing structures of all types.

This is a debate will continue for the foreseeable future as builders, code officials, and others evaluate designs and construction to resist the forces of Mother Nature.  If we work together, we can produce a rational, logical and economical solution to reduce the likelihood of recurrence of such a disaster.

Ed Sauter, Executive Director | Tilt-Up Concrete Association