It’s Time to Take a Modern Approach to Building in Tornado-Prone Areas

With the recent violent weather outbreak this weekend causing more tornado deaths in one weekend than the yearlong 2016 total, I am once again raising the issue of better building in tornado zones. First published in 2013, the Dual-Objective-Based Tornado Design Philosophy, defies traditional assertions that there is nothing you can affordably build to withstand tornadoes. Those rebuilding in the aftermath of the devastating storms have affordable options to protect their homes and families from future events.

This revolutionary engineering design concept emerged after Tuscaloosa, Joplin, and Moore tornado investigations. Adding $1 per square foot to the cost of construction to improve structural performance for property protection and incorporating tornado safe rooms for essential life safety can alter the pattern of death and destruction we continue to suffer. This weekend’s tragedy is more evidence that it is time to embrace a better way of building.

As noted in our paper, “Building Codes: The Foundation for Resilience” the American Society of Civil Engineers (ASCE), Federal Emergency Management Agency (FEMA) Building Science engineers, and leading academic researchers have called for a way of building to meet the challenge of saving lives while also preserving property in the face of tornado outbreaks.

The research-informed effort comes in response to field investigations that documented a pattern of disproportionate structure collapse in tornado outbreaks. They point out how even small design changes can make a difference, and they have developed guidelines to estimate the tornado-induced loads. This will provide reasonable targets for designers to use in their future work. Homes built to these newer, research-informed guidelines will have the advantage of better wall bracing, improved roof tie-downs, and overall stronger connections.

According to the newly released January 21-22 Southeastern U.S. Tornado Outbreak Report, published by the Wind Hazard Damage Assessment Group (WHDAG) of the University of Florida, the widespread catastrophic failures are not of themselves failures of engineering, but they are the inevitable result of policies that ignore tornado loads from minimum building design standards. It will be up to the populations in our communities (neighborhoods, towns, states) to decide whether to follow the lead of Moore, OK and implement tornado-resilient building codes in the future.

Dr. David O. Prevatt, Associate Professor of the University of Florida, Department of Civil and Coastal Engineering states, “If we can put a man on the moon, we can keep a roof on a house, and our research demonstrates it is possible to design and build houses that protect people and structures from deadly winds. Techniques developed and implemented in Florida that have reduced hurricane losses can be applied and used in houses to also reduce tornado losses.”

This approach is buoyed by the finding by the National Climatic Data Center (NCDC) that 95 percent of tornado damage occurs at EF-3 and below. Accordingly, the Dual-Objective-Based Tornado Design Philosophy enhanced practices can bring material increases in home strength. Moreover, since 90 percent of all tornadoes never exceed EF-2 with winds of up to 135 mph, wind-resistant building practices can dramatically improve building performance in nearly every tornado event.

This is possibly one of the most important breakthroughs in high-wind design during the past two decades, as it offers an affordable innovation that can potentially improve life safety and economic well-being for millions of residents throughout the U.S.

Homes are a long-term investment. Eighty percent of our homes are more than 20 years old, and most of them will be around for at least another 30 years. Therefore, it’s important not only for individual families to make careful choices now as they rebuild, but each community must acknowledge its responsibility to rebuild in a resilient way.

The Only Thing Worse Than No Mitigation is the Wrong Mitigation

LCH Blog Photo

After decades of effort, the marketplace for tornado safe rooms and shelters is finally rising. Consider that more than 3,000 tornado shelter permits have been issued in the City of Moore, Oklahoma since the March 25 tornado outbreak, and officials project that 7,800 Moore homes (40%) now have the essential safety feature.

Success here can be traced to relentless commitment to perfecting the building science by visionaries like FLASH Leadership Partner Dr. Ernst Kiesling and the FEMA Building Science team; strategic messaging by our many partners including the NSSA; and cost/benefit studies by noted economists like Dr. Kevin Simmons of Austin College.

The progress is significant, but enter the next challenge. Safe rooms aren’t as prevalent as they should be throughout all vulnerable areas yet, and not all tornado safe rooms are created equal.

So now that the market is responding, we must reemphasize the message that safe rooms and shelters should be constructed or fabricated to the most modern, stringent guidance or standards of either FEMA P-320, P-361 or ICC/NSSA 500. A nonconforming, poorly constructed safe room can do more harm than good by creating a false sense of security and putting families at risk.

For this reason, we took the opportunity at the 2015 NAHB International Builders Show “Home Safe Home Showcase” with our Legacy Partners FEMA and Portland Cement Association (PCA) to ask the questions that families want answered. The video series provides an overview of five types of safe rooms that can be built during new construction or added to an existing structure above-ground, below-ground, inside the home, outside in the garage, or in the yard.

Builders at the show were pleasantly surprised to learn that most types of safe rooms can be installed and completed in a day with the average cost for an 8-by-8-foot room from $8,000 to $9,500. Each offers different advantages, but all—when built right—provide the best available life safety protection against tornadoes. And it is essential that we point out the need to use a tested door.

One family knows firsthand the value of a safe room. Kevin and Sarabeth Harrison survived the deadly April 27, 2011 tornado that descended upon Athens, Alabama, by taking refuge in their concrete-block safe room with their two young children. The Harrisons have since moved to another home, installed another type of safe room, and have had to take shelter in that safe room during a tornado warning. We captured their inspirational story in our A Tale of Two Homes – Tornado, and it went viral, all the way to the National Building Museum “Designing for Disaster” exhibit.

Since then, the myth that there is nothing you can do to protect against a tornado has been under siege by accurate, life-saving information that a safe room is the right place to weather a tornado.

As stories of disaster survival often do, the Harrison video helps people understand that they can survive. Our new video series will help families understand exactly how to do it.

We Can Build Better in Advance of Tornadoes

In light of last night’s deadly tornadoes in Illinois, I am raising (again) the issue of building in tornado zones using the new, groundbreaking construction philosophy that emerged after the catastrophic Tuscaloosa, Joplin and Moore outbreaks from recent years. The engineering case is strong, and last week Dr. Kevin Simmons, an Austin College economist, added to the economic case as well – http://bit.ly/1auWHdu.

Clearly, it is time to spread the word to leaders that by adding $1 per square foot to the cost of construction and incorporating tornado safe rooms to homes in high-wind zones, we can forever alter the deadly pattern of death and destruction that follow the annual, typical tornado outbreaks that will continue.

Below are excerpts from our May 2013 paper, “Building Codes: The Foundation for Resilience” that describe the engineering breakthrough.

For more than three years, the American Society of Civil Engineers (ASCE), Federal Emergency Management Agency (FEMA) building science engineers, and leading academic researchers have called for a new way of building to meet the challenge of saving lives while also preserving property in the face of tornado outbreaks. Their work, published as the Dual-Objective-Based Tornado Design Philosophy, is landmark in that it defies traditional assertions that “there is nothing you can affordably build to withstand tornadoes.”[1]

The research-informed effort comes in response to field investigations that documented a pattern of disproportionate structure collapse in tornado outbreaks. They point out how even small design changes can make a difference, and they have developed guidelines to estimate the tornado-induced loads. This will provide reasonable targets for designers to use in their future work. Homes built to these newer, research-informed guidelines will have the advantage of better wall bracing, improved roof tie-downs and overall stronger connections.

According to Dr. David O. Prevatt, Associate Professor of the University of Florida, Department of Civil and Coastal Engineering, “If we can put a man on the moon, we can keep a roof on a house, and our research demonstrates it is possible to design and build houses that protect people and structures from deadly winds. Techniques developed and implemented in Florida that have reduced hurricane losses can be applied and used in houses to also reduce tornado losses.”

This novel new approach is buoyed by the finding by the National Climatic Data Center (NCDC) that even if a tornado is EF-4 or EF-5, 95 percent of the damage generated occurs at EF-3 and below. What this means is that the enhanced practices can bring material increases in home strength. Moreover, since 90 percent of all tornadoes never exceed EF-2 with winds of up to 135 mph, wind-resistant building practices like those included in the code can save lives and dramatically improve building performance in nearly every tornado event.

We believe that this is possibly one of the most important breakthroughs in high wind design during the past two decades as it offers an affordable innovation that can potentially improve life safety and economic well-being for millions of residents throughout the U.S.

Homes are a long-term investment. Eighty percent of our homes are more than 20 years old, and most of them will be around for at least another 30 years. Thus, it’s important not only for individual families to make careful choices now as they rebuild, but each community must acknowledge its responsibility to rebuild in a resilient way.

In January of 2015, during the International Builders Show, we analyzed and released updated NOAA Storm Prediction Center data showing that nearly 90% of U.S. counties experience tornado watches. This information underscores the point that the impact of building differently is not just beneficial to those who are directly hit by tornadoes. Having a stronger home and a safe room will bring beneficial peace of mind to all in harm’s way as they hunker down, worry, and wonder if their town will be next.

 [1] Van de Lindt, John W., et al. 2013. “Dual-Objective-Based Tornado Design Philosophy.” Available: http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29ST.1943-541X.0000622

Live from the 2015 International Builders Show – Give an Ordinary Room an Extraordinary Purpose

DSC_0461Last year, more than 50,000 attended the NAHB International Builders’ Show (IBS), and organizers are expecting an even larger turnout this week in Las Vegas for IBS2015. That’s why we’ve teamed up with our Legacy Partners FEMA and Portland Cement Association (PCA) to share three messages—tornado safe rooms save lives; tornado safe room options and price points are abundant; and tornado safe rooms present a win/win opportunity for builders and families alike.

As part of the show, we’re exhibiting outside the Las Vegas Convention Center with six types of safe rooms:

  1. Cast-in-Place Concrete Forms
  2. Concrete Masonry
  3. Insulated Concrete Forms
  4. Precast Concrete
  5. Steel and Plywood-Clad Wood
  6. Steel

The tornado safe rooms can be used above-ground, below-ground, inside the home, outside in the garage or in the yard. And, when built to FEMA 320 guidance, safe rooms provide “near absolute protection from winds up to 250 mph.”

We opened the exhibit today with a news conference for the builders, buyers, designers, and engineers. We defined the safe room growth trend as having three distinct drivers:

First, the high profile, deadly storms like Superstorm Sandy and tornado outbreaks of the past few years—Tuscaloosa, Joplin, Moore—have all galvanized public attention, driving home the point of how deadly weather truly is.

Second, the proliferation of weather information through expanded coverage, digital communication channels, minute by minute radar maps, and real-time severe weather alerting is increasing awareness.

(And we are contributing here with our smartphone app—FLASH WX Alerts with text to speech alert and the fastest and most precise performance to avoid over-alerting.)

So is there more weather, or are we just more aware?

Our Legacy Partners at the NOAA Storm Prediction Center in Norman, Oklahoma provided us with data on the average number of tornado watches from 2003 through December 2014. We wanted to identify U.S. locations affected by tornado watches.

The data indicates that, on average, nine out of ten of U.S. counties and the District of Columbia had experienced tornado watches, and of those, the average family spent 27 hours per year under a watch.

This is especially interesting because the affected area goes well beyond the ten states comprising the area labeled “tornado alley”[1].

The third driver, and perhaps the most relevant to our location at IBS2015, is that the marketplace is accelerating, expanding, and becoming better understood by consumers. More types of safe rooms are available. Distribution channels are expanding. For example, did you know you can now buy a tornado safe room online from The Home Depot? Cost options are expanding, and economists maintain their stance that safe rooms increase real estate value for homes in certain areas.

All of the above factors are making these life-saving rooms available to families no matter where they live. Hopefully families purchasing safe rooms never experience a tornado. Whether or not one affects them, they have invested in their families’ safety, comfort, and peace of mind knowing that the unthinkable happens and be ready for it.

It seems like an easy decision to us: invest in your home by increasing its value and potentially save the lives of your loved ones.

[1] As defined by the NOAA National Climate Data Center: “Although the boundaries of Tornado Alley are debatable (depending on which criteria you use—frequency, intensity, or events per unit area), the region from central Texas, northward to northern Iowa, and from central Kansas and Nebraska east to western Ohio is often collectively known as Tornado Alley.” http://www.ncdc.noaa.gov/climateinformation/extreme-events/us-tornado-climatology/tornado-alley