# Tornados and mobile homes **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [January 4, 2005, 3:23pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038 "2005-01-04T15:23:21Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![sjbdtz](https://avatars.discourse-cdn.com/v4/letter/s/b5ac83/32.png) [@sjbdtz](https://boards.straightdope.com/u/sjbdtz)\ **Post date:** [January 4, 2005, 3:23pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/1 "2005-01-04T15:23:21Z")
[http://www.straightdope.com/classics/a2\_096b.html](http://www.straightdope.com/classics/a2_096b.html) The chicken, or the egg. Which came first? I’m surprised that nobody has posited that the reason mobile homes appear to be more frequently targetted by tornados is simply that people, recognizing anecdotally that the region they inhabit is subject to somewhat frequent tornados, determine that the financial, and human, havoc caused by having their highrises and skyscrapers destroyed twice a year might be too much to handle. An alternative is that the only people remaining in tornado alley are those who couldn’t afford to get out, and get real houses. Granted this is somewhat more elitist, and non p.c., but considering that land values are lower in this area, it is another possible explanation. SJB ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [January 6, 2005, 4:33am UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/2 "2005-01-06T04:33:04Z")
…except that…tornadoes don’t damage skyscrapers and high-rises. As a matter of fact, I’d be hard put to it to name a single instance of a tornado damaging a skyscraper or high-rise. So I looked it up. Two. Broke some windows. [http://www.newton.dep.anl.gov/newton/askasci/1993/general/GEN018.HTM](http://www.newton.dep.anl.gov/newton/askasci/1993/general/GEN018.HTM) > [@](#): > > Most tall buildings are engineered with strong enough foundations and > steel framing to withstand tornado force winds. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [January 6, 2005, 4:34am UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/3 "2005-01-06T04:34:45Z")
Sorry, should’ve said “destroy”, not “damage”. ---
**Author:** ![hawthorne](https://avatars.discourse-cdn.com/v4/letter/h/c89c15/32.png) [@hawthorne](https://boards.straightdope.com/u/hawthorne)\ **Post date:** [January 6, 2005, 12:22pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/4 "2005-01-06T12:22:12Z")
Indeed, **DDG** , but **sjbdtz** ’s post is suggestive. Welcome to the Boards, by the way, **sjbdtz**. A WAG: To have had the capital to build high rises and skyscrapers that would withstand tornados you would have had to have enough to live and something left over to invest. Having to rebuild every now and then might have prevented the required saving, stopping communities from becoming big and rich enough to profitably build relatively tornado-proof buildings. ---
**Author:** ![bonzer](https://avatars.discourse-cdn.com/v4/letter/b/45deac/32.png) [@bonzer](https://boards.straightdope.com/u/bonzer)\ **Post date:** [January 6, 2005, 12:39pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/5 "2005-01-06T12:39:26Z")
> [@Duck Duck Goose](#): > > …except that…tornadoes don’t damage skyscrapers and high-rises. As a matter of fact, I’d be hard put to it to name a single instance of a tornado damaging a skyscraper or high-rise. There’s the Bank One Tower that’s still sitting derelict in downtown Fort Worth after being hit by a tornado in 2000. According to [this page](http://www.dallassky.com/fwtornado.htm) about it, the damage was such that the owners were unable to afford the necessary repairs and there was talk of simply demolishing the whole thing. Granted, this is hardly a tornado _destroying_ a skyscraper, but the damage has been enough to effectively end its economic life. ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [January 6, 2005, 12:52pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/6 "2005-01-06T12:52:26Z")
> [@bonzer](#): > > There’s the Bank One Tower that’s still sitting derelict in downtown Fort Worth after being hit by a tornado in 2000. According to [this page](http://www.dallassky.com/fwtornado.htm) about it, the damage was such that the owners were unable to afford the necessary repairs and there was talk of simply demolishing the whole thing. > Granted, this is hardly a tornado _destroying_ a skyscraper, but the damage has been enough to effectively end its economic life. Actually, if you follow all the way to the bottom, it’s being converted to apartments. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [January 6, 2005, 6:16pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/7 "2005-01-06T18:16:00Z")
Okay, but one or two instances of tall buildings being damaged by tornadoes hardly adds up to a hidden behavioral trend on the part of _homo sapiens_ to avoid building high-rises in Tornado Alley. I can think of a number of good-sized cities, with high-rises, or at least “very tall office buildings”, smack in harm’s way every spring (Kansas City, Springfields in IL and MO), and AFAIK none of them have a recurrent problem with tornadoes destroying high-rises, not to the extent of having to literally count the cost before building any _more_ high-rises in those cities, not to the extent of the prevalence of tornadoes being some kind of psychological deterrent. ---
**Author:** ![Skywatcher](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skywatcher/32/254_2.png) [@Skywatcher](https://boards.straightdope.com/u/Skywatcher)\ **Post date:** [January 6, 2005, 7:52pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/8 "2005-01-06T19:52:45Z")
> [@Duck Duck Goose](#): > > I can think of a number of good-sized cities, with high-rises, or at least “very tall office buildings”, smack in harm’s way every spring (Kansas City, Springfields in IL and MO), and AFAIK none of them have a recurrent problem with tornadoes destroying high-rises, not to the extent of having to literally count the cost before building any _more_ high-rises in those cities, not to the extent of the prevalence of tornadoes being some kind of psychological deterrent. How often do tornadoes strike high-rise areas anyway? ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [January 6, 2005, 8:47pm UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/9 "2005-01-06T20:47:43Z")
This line of argument seems to be sliding off the edge of logic. The Woolworth Building opened in 1913. Nearly all large US cities now were already large cities then. Even more so for the Seagrams Building (1958). What does a tornado do to an eight-story masonry structure? ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [January 8, 2005, 2:55am UTC](https://boards.straightdope.com/t/tornados-and-mobile-homes/283038/10 "2005-01-08T02:55:41Z")
My understanding is that masonry is pretty sturdy. In school tornado safety drills, you’re taught to look for masonry walls to hide behind. [http://www.clemson.edu/psapublishing/DISASTER/Tornado/Tornado1.htm](http://www.clemson.edu/psapublishing/DISASTER/Tornado/Tornado1.htm) > [@](#): > > DO NOT seek refuge in the following areas: Gymnasiums, auditoriums, dining halls, workshops, laboratories, classrooms, exterior rooms with windows, elevators, stairwells, non-masonry buildings, barns, utility areas, mobile units and mobile vehicles. Can’t find a reference to 8-story buildings, but I did find this. [http://www.april31974.com/indiana\_tornado\_data.htm](http://www.april31974.com/indiana_tornado_data.htm) > [@](#): > > The Monroe Central School was extensively damaged, but examination of the structure reveals that the principal failure mechanism was related to load bearing masonry walls. Figure 28 illustrates damage to the gymnasium area (near wing) and to classrooms (far wings). Load bearing masonry walls at the ends of the gymnasium failed (Ref. Figure 29). Although this failure compromised the structural integrity of the building the structural frame remained intact (Ref. Figure 30). Failures of masonry walls and failures of precast concrete roof units are also evident. Interior hallways away from areas with roofs supported on exterior walls and away from entrances would have been safe havens in this school. So the load-bearing masonry walls were damaged, but overall the structural frame survived intact. And… > [@](#): > > An old three-story elementary school at Kennard was heavily damaged (Ref. Figure 31). Although occupied by more than 100 persons at the time the tornado struck, no one was injured. Failures of load bearing masonry walls provided the basic collapse mechanism (Ref. Figure 32). First floor interior hallways were havens of refuge in this structure. So the outside was damaged, but the entire building wasn’t simply leveled, like a frame house would have been. [http://www.ncma.org/online/articles/Tornado.html](http://www.ncma.org/online/articles/Tornado.html) > [@](#): > > One of the most destructive storms to hit the state in recent years, the F-4 tornado plowed a path through the cinema demolishing one theater and lifting portions of roof or walls of two others. (Tornados are measured by the Fujita Scale. An F-4 tornado has wind speeds from 207 to 260 mph.) > > ``` > But the concrete masonry structure that shielded the town's youngsters from danger remained solidly in place. Shaffer's decision to move the children to the portion of the Van Wert cinema surrounded by concrete masonry walls saved lives. > > The Federal Emergency Management Agency encourages the addition of safe haven areas constructed of strong, impact resistant materials, such as concrete masonry, within homes and other structures located in tornado- and hurricane-prone areas. > > ``` [http://www.fema.gov/hazards/tornadoes/presskit1.shtm](http://www.fema.gov/hazards/tornadoes/presskit1.shtm) > [@](#): > > Use adequate ties to foundations and roofs when reinforcing concrete and partially reinforced masonry. Make ties between concrete and other materials with drilled-in fasteners or cast-in-place fasteners. > > Engineer and construct masonry walls to support the specific architecture of the building (i.e., exterior wall panels, parapets, and decorative finishes). Diaphragm action to resist wind generated shear forces must be maintained and reinforcement must be properly placed in concrete and masonry walls to reduce the possibility of collapse during high wind storms. The Fujita Scale does not address “damage to large masonry structures”. I would assume that this is because it doesn’t occur often enough to merit being put on the scale. An F5 tornado only removes frame houses, not masonry structures. [http://www.spc.noaa.gov/faq/tornado/f-scale.html](http://www.spc.noaa.gov/faq/tornado/f-scale.html) > [@](#): > > Strong frame houses leveled off foundations and swept away;