As with so many "is it possible" type questions, the answer of whether you can have a tornado-proof house is a resounding "well, yes, but." In this case, that sentence goes: "Well, yes, but it would be prohibitively expensive and ugly, and nobody really recommends you even bother."
What is tornado-proofing? According to the Federal Emergency Management Agency (FEMA), for a structure to be "tornado-proof" it must be, literally, missile-proof. The most damaging and unpredictable destructive force of a tornado isn't the swirling winds, it's the debris that the tornado picks up and hurls around, often at speeds in excess of 200mph. "Missile" is the right word when you're talking about a refrigerator flying through the air at 200mph.
The weak points in your house are windows and doors, obviously, but the most dangerous entry point may come as a surprise: it's your garage door. Garage doors aren't usually very sturdy, and if they blow down, the rush of wind can cause your house to become pressurized, like a can of soda. In extreme cases, wind can explode into the main house and blow down walls or even the ceiling. The other possible danger is in traditional insulation: air at this speed can cause serious damage, and if air can get between your walls at tornado-level speeds, they don't stand much of a chance.
Can you tornado-proof a whole house? Sure. You can live in a house made of solid concrete, with a steel door and no windows. You'd probably have to build it from scratch, though.
Uhhhh... Well, yeah, that doesn't sound like a real pleasant home to me, either. That's why nobody really tornado-proofs an entire house; it's expensive and for the 99 percent of the time that you're not being bombarded with a tornado, you'll hate it. But that's really the only way to fully tornado-proof a home: thick concrete, properly anchored in the ground, will withstand pretty much anything. There are lots of products that call themselves tornado-proof, from Pittsburgh Corning glass to reinforced concrete-and-styrofoam insulation blocks, and they're not bad ideas, but they're expensive and don't address many of the weakest points of a home. If you've got a garage, all the wildly expensive tornado-proof glazed glass in the world won't make your home impenetrable.
So what should you do FEMA does not recommend attempting to tornado-proof your home. Instead, it recommends a safe room: an internal room, like a bathroom or office or large closet, which can be modified to meet the International Code Council (ICC)-500 standard. ICC-500 is the product of a joint, decades-long effort by FEMA and Texas Tech University's Wind Science and Engineering department, known as WISE, to figure out exactly how best to protect a home from out-of-control winds.
You can view the complete document here, but in short, it requires that this room be fortified to withstand a 5 on the Enhanced Fujita scale, typically referred to as EF-5 level winds. EF-5 level winds are in excess of 200mph, so the FEMA code stipulates that the room must be reinforced, typically with concrete but sometimes with steel or even a combination of steel and wood.
Safe rooms can be retrofitted, but that can be very expensive, having to tear out walls and such. FEMA suggests, for a lower-priced option, to build an entirely new structure within the house, preferably in the basement or garage. It's not really the kind of project you want to do yourself; they have to be anchored in the ground, and the materials are necessarily difficult to manipulate. FEMA estimates that a family-sized safe room, which could double as storage or a closet, should cost around $6,600 to $8,700. There are theoretically programs to assist homeowners with this cost, although they won't cover the entire project.
Underground structures are generally preferable, but have distinct downsides: they may not be accessible to disabled people, and they can be flooded much more easily than above-ground shelters.
What about all that tornado-proof tech? There's a lot of interesting stuff out there that claims to be tornado-proof, from steel-reinforced hollow doors (which cost as much as an entire safe room) to a cabling system that anchors your home to the ground. Tornado-proof windows, like those from Pittsburgh Corning, are similar to bulletproof glass: it's usually laminated with a film and multiple kinds of glass, so it can stretch without shattering. Other materials, like polycarbonate, are sometimes used, though visibility is not usually quite as good as regular glass.
Tornado-proof glass isn't a prohibitively expensive retrofit, unlike many of these other improvements. But we have to go back to what FEMA recommends as the safest option: an aftermarket safe room.
I have observe speaking in ruff terms, that debry projectiles tend to fly sideways (missels), so tornado proof room might be one that is simuliar to the above structure, but underground.
I have not seen many tornados digging holes or ditches.
Though a flying car or tractor might come down directly, so the roof should be made strong enough to withstand this type of impact too.
Sounds like Tornado Shelters should be in the shape of a pyramid, flying things might be deflected!
Take a look at thin shell concrete domes like those at www.monolithic.com for a good candidate to replace the homes that were lost. These structures are capable of surviving earthquakes, hurricanes, wild fires, and even tornadoes. They cost about what a custom built home of the same square footage would go for depending on the interior finish. They are also extremely energy efficient.
Talk to Professor Michael Cobb, Physics Professor of Southeast Missouri University about the abilities of the domes and why they are so safe. Ask the Muscogee (Creek) Nation, of Okmulgee, Oklahoma about why they built a dome to house their school. Ask about the FEMA grants that can pay up to 75% of the cost of construction.
Just design a house that can be lowered underground.
Build homes underground with strong reinforced steel/concrete ceilings arched for supporting sod. They did that decades ago and those homes are bullet proof so long as you build on high ground away from flooding.
SIP construction can survive tornadoes (except for 200 mph fridges,of course) : http://www.noarkrcontrol.com/SIPs/projects/TN-Tornado.asp
Not only would building down instead of up help with tornadoes, they would be way more energy efficient.
And if done right can have lots of light and be "airy".
Whether a safe room or a whole house, Oklahoma has a risk scenario that doesn't quit just because you have one. The same construction design that could save yours or a family members' life in an eF-5 could then keep them from getting out alive if it floods. The tornado corridor is also a flood corridor, and even in a drought year there is still a lot of water just under ground level throughout many areas in the region.
Insisting on rebuilding--with taxpayer monies--right back in the middle of the same place the last building got leveled at should mean that YOU DONE BEEN HELPED. NEVER AGAIN. Not one penny. Just like the brain donors of St. Louis who refuse a floodwall.
There are more choices than WISE and the sole solution of a cenral shelter. We built about 1200 Archimede houses as beach resorts and ski resorts in 12 countries since 1981. Many were hit by earthquakes and hurricanes. In one instance, 24 of these built at Guana Bay beach in Sint Maarten were hit with the full fury of hurricane Luis on Sept 5, 1995. The hurricane just sat on the island for 12 hrs, destroying 80% of all the roofs, closing it to tourism for 2 years. The winds gusts were clocked at 240+ mph on that beach, sending many conventional concrete houses to the ground. And yet we suffered damage to the balcony railing only. It is true that we had just finished installing quality hurricane windows, but I was there during LUIS and can testify to the terrifying noise and bombardement by all sorts of projectiles. All trees lost all their leaves and concrete pools were floated out to sea.
So we have since improved on the concept to include tornadoes and tsunamis (incidentally Popular Science has an Archive piece on the system I patented in 1980: www.popsci.com/archive-viewer?id=iwAAAAAAMBAJ&pg=80&query=jacques%20poirier ).
I am preparing this web site ( see baja6.com) to add our tornado defense strategy to the other extreme defenses before August .
The main picture sort of insinuates that currently the answer is no.
jacques: Very interesting technology.So your method is sort of super SIP construction?
like Joan implied I am dazzled that anybody can profit $7249 in four weeks on the computer. have you read this web link Go to site and open Home for details
An architect’s point of view on tornadoes
I’d like to thank the author for an interesting article, but tornado-proofing your home does not necessarily require building a reinforced concrete bunker of a house. There are other alternatives to protect buildings, cheaper and more effective, which safeguard the integrity of the whole building.
There are two reasons for the destruction of buildings and death of people. The first one is that the way we live affects the life of our planet. Human activities with bursts of violence, wars, wrongly designed and placed buildings cause imbalance to the natural elements of the Earth, create energy blocks impeding the flow of the elements’ energy, namely, the air element.
In this connection we should remember the words of Max Hendel who said that "we live in a world which is governed by the laws of nature ... And we have no power to change these laws. If we know these laws and cleverly cooperate with them, the forces of nature become out best helpers. But if we act against them, they become the most dangerous enemies, capable of bringing awful destruction.”
For a designer, an architect, this means that even at the building design stage, one needs to take into account the influence of all these forces of nature as helpers.
The second reason, stemming from of the first one, is that the tornado airflow spinning at a high speed counterclockwise influences the gravity flows of entropic time, which are released by the space, attracts them to the Earth and focuses, keeps them near to it, while the tornado trunk is acting.
For a certain period these flows are stronger than the gravitational force produced by the Earth, which is why the overgravitation phenomenon occurs in the Tornado Alley region and all things that are on the land within the reach of the tornado trunk start to fall up.
In order to tornado-proof buildings, one needs to build outer walls on the basis of the radial symmetry principle and a roof pyramidal in shape slightly curved outwards with a light-weight multi-layer pyramid on the top which will be able to retain flows of time coming from the Earth above the building and will not allow the time flows coming from the space to pull the building up.
In order to reduce a tornado’s power in the usual tornado alleys and make it not so terrible, it is also necessary to create in these alleys a network of towers – light-weight metal structures at least 35 m tall, as a possible option, capped with special light-weight multi-layer pyramids and rings-bracelets around them. This network must be 350 x 350 m.
Destructive force of tornadoes in the regions where such towers will be placed can be reduced to 62%.
However, there is another, easier and cheaper way to solve the problem of tornadoes in combination with other problems.
Cottage-houses suffer destruction both from tornadoes as a demonstration of the air element’s force and the other elements such as fire, water, land. To eliminate all these threats together for one particular building, it is necessary to design and build energy-universal buildings so that they could "cooperate" with all the forces of nature.
It means that the shape of the roof and the shape of the exterior walls must be designed so that they could attract as a magnet the energies of all four elements at the same time, facilitate their passing rather than interfere with them. With the construction of energy-friendly-universal cottages, we won’t need any more special multi-layer pyramids to subdue tornadoes.
Architect Oleksandr Petrosyuk
Wow! What was that last comment about? Too bad these comments aren't edited a little bit more.
For my money the Monolithic dome has it in spades. You can bury them if you want to. I'm sure it would be easier to bury a monolithic dome than any other type of structure. Just let the engineers know what your plans are.
However, that is an added expense. Most people don't want to live underground. Most people want windows. I would suggest storm shutters, and storm doors.
I am disappointed with the author’s assertion that we shouldn't bother trying to do better because it is:
"prohibitively expensive and ugly, and nobody really recommends you even bother."
It’s important to protect yourself, your family, your hearth and home. As an adult I don’t want to rely on the government to protect me from storms. That’s my responsibility. The dome will lower your insurance rates as well. The author needs to reconsider the importance of storm proofing your house.
No I don't have one yet, but I sure want one. Attitudes like the autor's make it hard to think ouside of the box.
As the above reply mentions, monolithic domes can be both beautiful and effective. The website http://www.MONOLITHIC.com lists their wind resistance at up to 700MPH. My dream is to build such a dome atop a mountain, of which there are plenty in my local area. There are two such domes within 20 miles of here; they're both well-built, they look great and they blend well with the surrounding landscape. I don't know where the author obtained his information, which reads more like an opinion piece than a well-researched article. But, a quick visit to http://www.monolithic.com will reveal the weaknesses of the author's claims in short order. By the way, most of the heavier debris that is flung by tornados only reaches shallow heights. And, the reinforced concrete walls of a monolithic dome will provide the best protection against such air-borne 'missiles'. Of course, nothing is surefire/foolproof. But, if you have the money to build such a structure, then, why not do so, especially if you live in an area prone to natural or manmade disasters?!