STORM-PROOFING YOUR HOME I

Man1: It looks like a war zone. I've been in law enforcement for 34 years and I've worked three different tornadoes. I've never seen one as devastating as this.

Michael Holigan: May 27th, 1997, Jarrell, Texas. An F5 tornado, nature's rarest and most powerful twister, tears through the town. With winds estimated at over 200 miles an hour, even the experts were amazed at what happened.

Man2 This was total, I mean, this was a total devastation. I had never seen an F5 or the results of an F5 tornado. I'd seen F4's and there's a difference.

MH: Twenty-seven people were killed and the little town was devastated. Houses were scraped clean off their foundations with nothing left behind.

Ernst Keisling: The houses in Jarrell were sitting on an open plain - no privacy fences and most of them were struck from the front with a double garage door there by a wind that was undiffused and undeflected.

MH: Dr. Ernst Keisling runs the Wind Research Center in the Civil Engineering Department of Texas Tech University. He and his associates are looking for new ways to protect people and their property from storms like the Jarrell tornado. They have built an air cannon that can hurl objects into structures at up to 120 miles per hour - the speed reached by debris in the strongest of tornadoes.

EK: Our focus has been two-fold. One is to protect people during severe wind events and the other is to reduce property damage.

MH: Dr. Keisling and his researchers have constructed dozens of sections of exterior walls - mockups of the kind of walls found on houses all over the U.S. In this basement lab they put them to the test. There's the standard wood frame wall with lap siding, very common construction in the Midwest and Northeast. So pretty much your typical wood frame house doesn't hold up too well, or something.

EK: That's correct. Most any conventional construction would behave in about the same way. The missile simply perforates.

MH: We had normal lap sidings and a piece of wood right up against the stud, so it even rubbed up against that. That stud wouldn't stop it all either.

EK: No, if it were to hit the stud it would simply break the stud and, of course, do more global damage to the whole wall section, but that still would not begin to stop the missile.

MH: So a typical house isn't real safe from flying projectiles.

EK: No.

MH: People always tell me that they want a brick home because they're stronger. That's not really true. Brick does look great, and it does last a long time, but it doesn't support the weight of your house and it's not designed to take high impacts. This is a typical brick wall set up and we have our 2x4 stud back here. Got a little exterior sheathing and we've got a brick cavity and then we've got the brick itself. And as you're going to see, like I said, it's not designed to take heavy impacts. Well it doesn't look like the brick wall held up much better than our wood wall, did it?

EK: You're right. There's simply not enough structural integrity or continuity there to avoid this kind of behavior.

MH: The greatest danger to people in a hurricane or tornado comes not from the wind itself, but from the flying debris the storm picks up and slams into whatever happens to be in its way. The secret to staying safe in these storms is to put as many strong walls as possible between you and those flying missiles. So what kind of wall do scientists recommend? A simple, inexpensive cinder block wall with concrete inside and reinforced with rebar seems to hold up the best. This wall has withstood over 20 hits at speeds at up to 100 miles an hour. Definitely different from the other walls where it went straight through. I could see where a family and their valuables would be protected in a home like this.

EK: Yes.

MH: And any brick mason could actually build a wall like this.

EK: It should require no new technology nor any additional subcontractors.

MH: It's just basically eight-inch concrete block and then you dropped rebar down in it and poured concrete in it.

EK: That's correct. And it's easily anchored to the floor too in new construction by just leaving bars sticking out of the slab.

MH: The wind research scientists at Texas Tech have developed detailed plans for constructing these safe rooms, both for retrofitting rooms in existing houses and for adding these features to new homes. They've come up with three different models for a safe room, depending on your budget.

EK: So our focus in occupant protection has been on making a small room within the house safe for occupants and we typically choose a small room, such as a closet or a bathroom, because it's very affordable to harden and stiffen that.

MH: Scientists are working hard to find new ways to keep you and your family safe from flying debris and the dangers of nature's most violent storms. But they're also studying inexpensive and simple things you can do when building your house to make sure you keep a roof over your head when nature gets out of hand.

Contacts:
Security First Dist., Inc.: 888-261-5533

Episode 58 1997 - 98 Season

| Storm-Proofing I | Storm-Proofing II | Garden Trellis | Bankruptcy | Pruning Paint |

Purchase Video