Chris Ramseyer is director of the Fears Structural Engineering Lab at the University of Oklahoma.
Yes. Tornadoes shouldn’t be exempt from codes that protect residents.
As a structural engineer, I believe in a life-safety approach to the design and construction of our buildings. This philosophy places a premium on lives and is successful when the occupants walk away from the structure without injury, even if that structure is destroyed by a natural disaster.
Seismic events like earthquakes, which occur with absolutely no warning, have been considered in design codes for decades. Along coastal regions, designers and home builders are now required to meet certain guidelines for safety against hurricanes and high water. So how is it that tornadoes have been neglected for so long when planning the safety of residents?
In Oklahoma, occupants receive warnings up to an hour before a potential tornado hits, which is plenty of time for them to get to a shelter if one is available. While protecting lives by fortifying an entire building would be extremely expensive, protecting lives with a simple tornado shelter could be done at a reasonable cost.
A simple in-ground shelter can be installed in Oklahoma for as little as $2,500. If all new homes were required to have tornado shelters, a competitive price advantage—or rather, disadvantage—among builders would not exist. And if a builder wanted to differentiate its products from the norm, it could upgrade its options by offering above-ground safe rooms. (Prices typically start in the $8,000 range.)
This kind of mandate is consistent with our life-safety design philosophy in that a tornado shelter protects humans, not property.
There is considerable impetus and positive sentiment—mine included—for states or local jurisdictions to make storm shelters or safe rooms mandatory in new public buildings for K–12 schools, colleges, and day care centers located in high-risk areas.
Alabama has had good results with such a law, as have municipalities such as Omaha, Neb. The 2015 International Building Code likely will specify safe areas for new schools built in high-risk regions.
Mandatory safe area laws also are appropriate for new multifamily housing such as nursing homes, mobile home parks, and rental apartments. Tenants should expect to pay a major portion of the cost of providing protection. Public funding could subsidize low-income families.
But shelters should not be mandated for privately owned single-family or multifamily residences. Innovations and building improvements are most successful when driven by owner involvement and buy-in. Mandating shelters increases initial housing costs in an already price-sensitive marketplace, removing priorities in making purchases. Storm shelters and performance-enhancing improvements should be regarded as investments that provide safety, peace of mind, and improved resale.
Private selections of storm shelter types and sizes should be accorded by building owners. Incentives such as property tax credits, financing, or competitive grants are encouraged and will stimulate business activity.
Builders, government agencies, professional societies, and housing-related trade associations should present reliable information on available technology and their costs. That information also should strive to dispel falsehoods—like exaggerations about tornado wind speeds and claims that underground shelters are safer than well-built aboveground safe rooms—heard after the recent severe weather events in Oklahoma.
Learn more about markets featured in this article: Oklahoma City, OK.