University of Dayton engineering professor Joseph Saliba (right) and a Van Wert, OH Habitat for Humanity volunteer discuss the value of "hurricane clips" in reducing wind-related storm deaths and property damage. Dr. Saliba was one of several expert presenters at a Dec. 10 FEMA workshop on Wind-Resistant Building held in Van Wert-one of several NW Ohio cities which suffered major damage in recent tornadoes.
• Hazards: Tornadoes
• Tornado Safe Rooms
• Recommendations to Better Protect From Tornado Damage
Van Wert, OH -- Attendees at a Wind-Resistant Construction Workshop here Tuesday were told that incorporating wind resistant techniques during rebuilding from tornado damage "can make a life and death difference."
The Federal Emergency Management Agency (FEMA) and Ohio's Emergency Management Agency (Ohio EMA) recruited mitigation experts to offer tornado-damaged Northwest Ohio residents and local contractors technical guidance on how to rebuild more wind-resistant structures at the workshop.
During a thunderstorm, blizzard, hurricane or tornado, the force of wind on a house works in several ways:
- Horizontal wind pressure causes "tilt" - such damage also is called a "shear."
- Horizontal wind pressure also can cause a structure to move off its foundation - called "sliding."
- Lateral force can cause a home to rotate off of its foundation - this is called "overturning."
- Wind flowing over a building can result in the roof being ripped from the structure - this is called "uplift."
Instructors from FEMA and the Ohio Emergency Management Agency highlighted the value and affordability of adding a specially-reinforced "tornado safe room" when rebuilding storm-damaged structures. They also demonstrated how using readily-available metallic clips (often called "hurricane clips") and straps can reinforce the connections between structural components-- roof to walls and walls to understructure -- thereby redistributing wind pressures from a structure's frame to its foundation.
"We know from experience that safe rooms save lives," said Dr. Joseph E. Saliba, University of Dayton engineering professor and a featured speaker at the Van Wert workshop.
"In a typical year, Ohio has at least six storms with winds of 90 miles per hour or greater," said Saliba. "In those conditions, hurricane clips and other wind resistant techniques can make a life and death difference."
Additional information on wind-resistant building techniques may be found on FEMA's Website at www.fema.gov/library/prepandprev.shtm and at a Website maintained by the American Society of Civil engineers: http://www.asce.org.