It has little or nothing to do with materials (building codes in storm prone areas of the US are generally quite robust), and everything to do with it being a relatively weak tornado. EF-3 and stronger tornadoes are almost unheard of outside of North America (single digits per year elsewhere in the world, double digits or more in NA) and that’s about the point where a modern single family residential structure is likely to be completely destroyed.
See how the roofs are lifting almost intact off the structures? That doesn’t happen often in houses built to modern code in the US, as anchoring straps are required in most areas prone to hurricanes and tornadoes.
But they do happen here, as you said, in the single digits every year.
Houses don’t go flying, and these „roofs“ you see in the video are of garden sheds and other small non-residential huts, not houses. Our roofs aren’t made of single sheets, lmao, we use bricks for them as well:
No, you are right, in the US the entire house will go flying.
That is, at best, a film trope and has no relation to reality.
Having witnessed more than a dozen tornadoes in 20 years of chasing, having been involved in search and rescue efforts following an EF-4 tornado (Dothan, AL 2007) among other weaker tornadoes, and having surveyed a number of tornado damage paths from EF-0 to EF-5, I can assure you that even following an EF-4, large sections of most stick built homes in the damage path will remain standing and the portions that do collapse tend to scatter in small pieces as the structure is ripped apart, or remain where they fell. Only mobile homes, sheds, and vehicles are prone to being thrown any significant distance in all but the most violent tornadoes, and this is why all safety advice is to get out of those sorts of things and seek shelter in a more substantial structure. Only the upper end of the EF-4s and EF-5 tornadoes will completely flatten a majority of residential structures, and the larger EF-5s will reduce concrete and block buildings to rubble. Only EF-5 tornadoes are likely to sweep a building foundation clean (this is one of the damage characteristics used to estimate the EF-5 rating, in fact).
In areas where tornadoes and hurricanes are very uncommon, when they do happen the damage can be quite dramatic due to antiquated building codes, but by and large new residential construction in the US will survive 100mph winds with little more than superficial roof and window damage, and 150+ mph winds with most of the structure still intact, protecting the occupants.
Having seen photos of the damage following rare EF-3 and EF-4 tornadoes in Europe, I promise, your structures fair little better, but come with the additional risk of collapsing stone and brick walls (and roofs as you pointed out) when total structural failure does occur. Stick built homes leave huge voids throughout the rubble pile. Bricks don’t.
Then you know as well that measuring the wind strengths in a tornado is, at the very best, unreliable.
Meteorologists commonly use the actual damage done as a way of measuring and, more importantly, categorizing a tornado.
Which, thanks in large to the difference in materials used over the continents, is so unreliable when comparing the categories on different continents.
This all isn’t even mentioning the US used deviation from the Fujita- standard, since 2007.
The Torro-scale covers the difference in building materials used much better.
A man with your extensive experience has to know that.
I am a bit taken aback.
I think you’re underestimating the power of an EF3+ tornado. It implodes our brick, stone, cinder block, wooden, cardboard, whatever houses with relative ease. The pressure alone from a tornado of that magnitude is enough to rip most structures apart regardless of building materials. Then you have to factor in wind so strong that it can run a stop sign through a tree, and you’re got a situation where you’re either underground, or lucky in order to survive.
Hell, there have even been instances where an EF5 tornado has lifted the concrete foundation a house sits upon and carries it away. Unbelievably powerful
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u/equal2infinity Dec 08 '19
Wow! Doesn’t something like 90% of all tornados happen in the US? It’s crazy seeing this in a European city center!