Will the Tornadoes Affect Codes?

Christina Lewellen
May 25, 2011
THE TALK... | Codes & Standards
We have seen some unbelievable images coming across the news wires following the devastating tornadoes in Missouri this week.  Those storms follow on the heels of an equally destructive tornadoes in Alabama, as well as other storms across the country. Some window and door companies were directly impacted, including Lincoln Windows in Wisconsin, and our hearts certainly go out to all of the people who have lost homes and loved ones as a result.
Just as Hurricane Andrew had significant and far-reaching effects on building codes in Florida and throughout the Southeast following its devastation in Florida nearly 20 years ago, I would imagine that the most destructive tornadoes we’ve seen in a generation in Alabama and Missouri could impact code discussions moving forward.
Do you think that's possible? Is the impact of these recent storms significant enough to warrant code changes? Will window and door requirements for residences and buildings in “tornado allies” be stricter in the coming years? Post a comment or send me an email to share. How will these storms impact fenestration products in these regions as they’re rebuilt?
 

Survey Results for 05/25/2011:

 

Will recent tornadoes lead to changes in building codes?

 

Possibly, but I'm not certain.

  

 

34%

Yes, we are likely to see stricter codes.

  

 

33%

No

  

 

33%

 

Wow! I can't remember a poll so evenly split. I guess we're not quite sure how the recent storms will impact future codes.

“No I don’t see the codes changing dramatically simply because the cost to build a structure strong enough to withstand 200 MPH winds would be astronomical,” writes one reader. “Also, a tornado’s path is typically blocks to one mile wide or so and the chances of such a destructive storm hitting that exact same area are slim.”
Another reader, Wayne Gorell of Gorell Windows & Doors, suggests that hurricane windows should really be called storm windows—but that phrase is already used to identify something else.
“When someone says storm windows, people think of the aluminum ‘secondary’ exterior window that was very popular twenty plus years ago,” he wrote in a recent blog. “But with the rash or strong thunder storms and tornadoes devastating much of the country, STORM (hurricane) windows are what many people need. With the common nomenclature being hurricane windows, many people only think of these types of windows for hurricane-prone areas. They really are quite valuable to homeowners in most of the country.”
While hurricane products, having gone rigorous testing, are likely to stop most windborne debris, he writes, nothing could have protected many of the homes devastated by recent storms. Still, for homes on the periphery of the storm’s path, this level of protection could have helped.
So will all of this result in code changes in Alabama or Missouri? The poll is mixed, as are the readers who wrote in. “Codes are sure to change in Tornado Alley,” asserts one reader.
Time will tell.

By the way, here's a resource from AAMA, for those who would like more information:

In April, AAMA released AAMA 512-11, Voluntary Specifications for Tornado Hazard Mitigating Fenestration Products which uses existing test methods and other procedures to qualify specially designed windows and other glazed fenestration products for tornado hazard mitigation. The newly released document provides a system for rating the ability of windows to withstand impact, pressure cycling and water penetration, which are generally associated with tornado conditions.
 
The specification outlines that different levels of protection apply to different buildings such as, but not limited to, hospital emergency rooms, community shelters and police/fire headquarters. These levels of protection are specified based on requirements of the authority having jurisdiction, and each level corresponds to different testing requirements. The level of testing required for each of these types of facilities also depends on the FEMA performance zone where the building is located, as the weather conditions and likelihood of a tornado varies depending on the part of the country.
 
The recent tornados and severe weather have made it clear that there is a need for building design to have an eye towards possible tornado damage or other severe weather conditions. AAMA 512 meets this need for a specification that should positively influence building design, and we will continue to work to meet similar needs for building standards.
 

Contact Christina Lewellen, senior editor, at clewellen@glass.org.