The National Weather Service and a national building expert are questioning why homes in Tennessee that should withstand lesser tornadoes are instead collapsing or flipping over.
The most recent example is a home in Christiana, that on Nov. 6 was torn off its foundation and flipped over, killing 41-year-old Angie Walker.
When investigators with the National Weather Service went to the scene, they used what’s called the Fujita Scale, which ranks the strength of a tornado based on the damage, with 5 being the strongest and 0 the weakest.
According to the Fujita Scale, the tornado was only a EF2, and should have only resulted in roofs torn off houses and broken branches on trees.
Krissy Hurley, warning coordination meteorologist with the National Weather Service, said trees were still standing by the house and the surrounding damage wasn’t devastating.
The house, though, was completely flipped.
“So this shouldn’t have happened to this house?” asked the News4 I-Team.
“In theory, it shouldn’t have,” Hurley said.
On Feb 28, when a similar EF2 tornado hit Clarksville, Hurley also noticed something similar that troubled her.
Hurley took photographs of a house that had been torn off its foundation, yet two trees that stood directly in front of the home remained.
“That didn’t add up to you?” asked the News4 I-Team.
“No. That definitely did not,” Hurley said.
The News4 I-Team consulted with the Insurance Institute for Business & Homes Safety, a non-profit that studies how to make homes stronger in the wake of natural disasters.
We found the homes that collapsed in the lesser tornadoes were built up to code.
But Susan Millerick, director of public affair for IBHS, questions if the codes are strong enough.
“We think the codes should be much higher,” Millerick said.
According to a demonstration by the IBHS, it takes speeds of 115 miles per hour to completely tear a home off it’s foundation.
The News4 I-Team found in Tennessee, homes are only required to be built to withstand wind speeds of 90 miles per hour.
So even if the Fujita Scale states that a lesser EF2 tornado, bringing winds of 115 miles per hour, should not destroy a house, if it happens to a home in Tennessee, it will likely collapse.
“Are the homes in Middle Tennessee in great danger of falling in even these lesser tornadoes?” asked the News4 I-Team.
“It's not so much, that we're not building properly. We believe we believe we can build stronger. But we're building ourselves into much risker places,” Millerick said.
Millerick pointed to a study released in October by the journal Climate and Atmospheric Science, which tracked where tornadoes are increasing across the U.S.
The study showed more tornadoes are appearing in the Midsouth, with Middle Tennessee right on the border.
The IBHS has a range of suggestions on how to better build your home to withstand a tornado.
The News4 I-Team is currently investigation why the state’s wind speed standards are so low and will update with any new information.