Tornado damage

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stevenf
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Tornado damage

Postby stevenf » Thu May 26, 2011 8:15 pm UTC

In the UK the majority of houses are built of brick, stone, slate, tile, concrete etc. on the outside (and on major internal walls) and timber, plaster etc. inside. We do have some timber framed houses, especially the newest ones.

Looking at the horrendous damage that can be done to a timber frame house by a few seconds exposure to a tornado I was wondering why, in the tornado affected states, the building codes are not creating more resisitant structures.

Would a tornado resistant structure be impossible or too expensive? Come to that, how would our housing stock react to a tornado?

I suspect that earth sheltered buildings might have something going for them - also cooler in summer and warmer in winter.

The Dutch are going for floating houses in quite a big way. Any sign of that catching on in the flood prone areas of the USA?

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Re: Tornado damage

Postby Azrael » Thu May 26, 2011 8:38 pm UTC

Just off the top of my head, I think you're significantly over-estimating how strong your typical residential brick-walled building is when compared to a tornado. Nor is roofing technology all that discrepant between building styles.

Secondly, the probability of actually being struck by a tornado is pretty low because the incidence zone is downright huge:

Image

I doubt it would be economically justifiable (let alone practical in any sense) to try to storm proof the housing stock in that large an area. Especially considering just how tremendously stronger you'd have to get -- think either entirely underground or concrete bunker -- to be tornado 'proof'. Never mind trifles like building code improvements are rarely retroactive.

There's a potentially useful model in many hurricane-prone coastal areas where there are strict rebuilding requirements for homes that are in flood plain and storm paths and are likely to be damaged again -- but the probability of being struck twice by a tornado is much, much lower. Even those aren't exactly code-driven; the advanced requirements are legislated by Federal flood insurance programs, and since there are no commercial entities willing to remain in the business people are required to build in certain ways to get the insurance necessary for mortgages, loans etc.


Regarding flooding: A similar issue with scale exists:

Image

While certainly not every house in that watershed is prone to flooding, each of those rivers experiences flooding problems. Adapting to flood proof relevant homes is a massive undertaking.

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Re: Tornado damage

Postby DSenette » Thu May 26, 2011 8:54 pm UTC

you forgot to consider that many (probably most?) of the homes in the UK are also really old (comparatively) and in no way built to any kind of "storm resistance" i don't think the houses there would fair as well as you think.

when struck directly by an F5 tornado, being in a brick home isn't really going to do that much for you (they all get leveled). for a building to completely survive a direct hit by a really large/powerful tornado it has to be a pretty sturdy building, and usually it has to be SPECIFICALLY built to resist an F5 tornado (or more likely something like a bomb or plane crash....like a nuclear power plant), that usually involves a LOT of concrete and rebar and a very specific shape. not exactly something most people want to live in.
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Re: Tornado damage

Postby LaserGuy » Thu May 26, 2011 9:09 pm UTC

You also need to pick your battles a little bit. A stone house might be better protection against tornadoes, but if you are in an area also known for earthquakes, you may be better off with wood.

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Re: Tornado damage

Postby fr00t » Fri May 27, 2011 12:56 am UTC

The odds of getting hit by a powerful tornado are so infinitesimal that any significant concession in the way of expenditure is stupid.

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Re: Tornado damage

Postby iChef » Fri May 27, 2011 2:32 am UTC

Here is the US almost all of our houses are wood frame. If you want to build something tornado resistant your best bet is reinforced concrete. I have no idea how much that would cost compared to a regular frame house. Really when you are talking an F5 tornado your best protection is prayers and a good insurance policy. Brick and stone buildings won't fare much better than wood, you need something heavily reinforced with steel. Although if you didn't mind living in a bunker type house if you build a 3 story reinforced concrete building it could work very well. Bed rooms and some storage on the top floor. Garage, laundry and utilities on the bottom. If a tornado hits it will probably remain standing. If you get a flood just pull everything up to the top floor and when you get home get out the bleach and a hose and just scrub the concrete clean. I would like to live in something like that, but I live a fairly Spartan, utilitarian lifestyle anyway. I highly doubt many Americans would want to live in what is essentially Soviet block housing.
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Re: Tornado damage

Postby podbaydoor » Fri May 27, 2011 2:44 am UTC

Just to point out, a Home Depot and other big-box stores in a strip mall area in Joplin were literally flattened by the recent tornado. EF-5s have winds going excess of 200 miles per hour (321.86 km), even buildings that you'd think are sturdier than a wood-frame home are susceptible.

People have been commenting all week on mandating storm shelters and the like, similar to this topic. Biggest issue? Cost. Areas in the Midwest and South are the most poverty-stricken areas in the US, there is only so much you can do to force people to shell out several tens of thousands of extra dollars for a house. That's not even addressing the tornado's special affinity for mobile homes.
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Re: Tornado damage

Postby stevenf » Fri May 27, 2011 8:40 am UTC

Thanks to all contributors.

Such tornados (and earthquakes) as we get in the UK are vanishingly slight compared to the stateside versions. At most there are a few slates off and and a tumbled chimmney stack or two. Annual weather related deaths can be counted on one hand usually. The most recent here in the north involved a teenage girl being crushed in a car by a falling tree last week.

The highest windspeed we have had on the exposed Northumbrian hilltop where I live in the last two decades was 88mph - that was the night the ridge tiles came off.

In the UK press it was reported that all that was left of a bank in Joplin was the concrete vault - what proportion of people have a concrete bunker to hide in in their homes?

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Re: Tornado damage

Postby DSenette » Fri May 27, 2011 12:21 pm UTC

stevenf wrote:Thanks to all contributors.

Such tornados (and earthquakes) as we get in the UK are vanishingly slight compared to the stateside versions. At most there are a few slates off and and a tumbled chimmney stack or two. Annual weather related deaths can be counted on one hand usually. The most recent here in the north involved a teenage girl being crushed in a car by a falling tree last week.

The highest windspeed we have had on the exposed Northumbrian hilltop where I live in the last two decades was 88mph - that was the night the ridge tiles came off.

In the UK press it was reported that all that was left of a bank in Joplin was the concrete vault - what proportion of people have a concrete bunker to hide in in their homes?

88Mph?.....there wasn't a delorian at the front of that wind was there?

podbaydoor wrote:Just to point out, a Home Depot and other big-box stores in a strip mall area in Joplin were literally flattened by the recent tornado. EF-5s have winds going excess of 200 miles per hour (321.86 km), even buildings that you'd think are sturdier than a wood-frame home are susceptible.

People have been commenting all week on mandating storm shelters and the like, similar to this topic. Biggest issue? Cost. Areas in the Midwest and South are the most poverty-stricken areas in the US, there is only so much you can do to force people to shell out several tens of thousands of extra dollars for a house. That's not even addressing the tornado's special affinity for mobile homes.
not to mention the relatively shallow water table in most of the southern states.....can't ALWAYS build an underground bunker, unless you're cool with it being filled with water
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Re: Tornado damage

Postby Cheezwhiz Jenkins » Sun May 29, 2011 6:59 pm UTC

podbaydoor wrote:the tornado's special affinity for mobile homes.


Surely you're being tongue in cheek...?
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Re: Tornado damage

Postby podbaydoor » Mon May 30, 2011 6:15 pm UTC

Yes. But it's anecdotally true (perhaps statistically, but I don't know if that kind of data has been put together) that mobile homes are damaged a great deal more often by tornadoes. First, because swathes of Tornado Alley are rural, which have more mobile homes, and second, because mobile homes are much more fragile, with no real foundation.
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Re: Tornado damage

Postby ++$_ » Mon May 30, 2011 8:42 pm UTC

Mobile homes are damaged more easily by wind than houses with foundations -- they can be rolled over by winds as low as 60 miles per hour, which gives you an idea of how much less resilient they are than permanent houses. Since they are damaged by lower wind speeds, a small tornado of F0 or F1 strength can do serious damage when it would have had a negligible impact on a permanent structure. F0 and F1 tornados are vastly more common than powerful tornadoes.

In addition, in any tornado, the radius of winds that can damage a mobile home is much larger than the radius of winds that can damage a frame house.

Data: On average, 1/3 of fatalities occur in mobile homes, even though mobile homes make up less than 20% of all housing units.

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Re: Tornado damage

Postby KestrelLowing » Tue May 31, 2011 7:12 pm UTC

I could be talking out of my butt, but also doesn't it have a little to do with the locations of mobile home parks? Often there isn't much around them and it's quite easy for a tornado to come ripping across opposed to other places that have hills and other natural barriers.

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Re: Tornado damage

Postby savanik » Tue May 31, 2011 8:40 pm UTC

I've never understood why people wouldn't want to live in someplace that looks like these. I have a friend who has one in Oklahoma, they say their worst problem is finding shelves that fit.

Many homes in this style are rated up to EF4 tornado winds. EF5 and above - your mileage may vary.

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Re: Tornado damage

Postby Cheezwhiz Jenkins » Tue May 31, 2011 9:26 pm UTC

podbaydoor wrote:Yes. But it's anecdotally true (perhaps statistically, but I don't know if that kind of data has been put together) that mobile homes are damaged a great deal more often by tornadoes. First, because swathes of Tornado Alley are rural, which have more mobile homes, and second, because mobile homes are much more fragile, with no real foundation.


Well, they're certainly damaged to a greater degree than a brick-and-morter house (as I can attest from first-hand experience). Just making sure you were saying it's because mobile homes are more fragile, not because they "attract" tornadoes - I've talked with folks who actually believe that. Never have gotten an explanation yet as to how that is supposed to work.

KestrelLowing wrote:I could be talking out of my butt, but also doesn't it have a little to do with the locations of mobile home parks? Often there isn't much around them and it's quite easy for a tornado to come ripping across opposed to other places that have hills and other natural barriers.


Not really. Hills and mountains are not barriers to tornadoes. Unfortunately.
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Re: Tornado damage

Postby podbaydoor » Tue May 31, 2011 11:17 pm UTC

Oh, I don't actually believe it. It's a pretty common joke around here.
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Re: Tornado damage

Postby Diadem » Tue May 31, 2011 11:40 pm UTC

Little known fact: The Netherlands actually has the most tornadoes of any country in the world. Most people when they learn of this fact are extremely surprised. The Netherlands is not known for its tornadoes. But that is because most tornadoes here go by entirely unnoticed. The damage an F1 or F2 tornado causes is essentionally zero.

Admittedly the US tornadoes are heavier on average. But even counting heavy tornadoes the difference between the US and other countries is not as big as you'd expect. A single tornado in the US just causes enormously more damage than in Europe. And this is entirely because of Europe having better buildings.

Yes even most Dutch houses will probably get damaged in an F5 tornado. But let's not pretend all tornadoes are F5.
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Re: Tornado damage

Postby Dark567 » Tue May 31, 2011 11:48 pm UTC

The worst tornado in the history of the world killed 1300 people(China), where as hurricanes, earthquakes and tsunamis do have a lot more. There have been heatwaves in the US that have caused far more damage then tornadoes, and any money spent on tornado-proofing would almost certainly be better spent on hurricane and flood proofing houses. Just look at the number of people killed in different disasters.
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Re: Tornado damage

Postby Diadem » Wed Jun 01, 2011 12:18 am UTC

The two are not mutually exclusive. In fact sturdier homes will fare better against tornadoes, floods and hurricanes. They will also be safer against fires, lightning strikes, tsunamis, chemical disasters, even buglary and arson. And if insulated well they save you on your power bill.
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Re: Tornado damage

Postby ++$_ » Wed Jun 01, 2011 1:01 am UTC

Diadem wrote:Little known fact: The Netherlands actually has the most tornadoes of any country in the world.
By unit area, you mean.

The number of tornados per square mile per year in Oklahoma and Kansas is pretty comparable to that in the Netherlands.

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Re: Tornado damage

Postby Cheezwhiz Jenkins » Wed Jun 01, 2011 1:13 am UTC

podbaydoor wrote:Oh, I don't actually believe it. It's a pretty common joke around here.


Ah, okay. Must...learn...jokes...
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Re: Tornado damage

Postby Azrael » Wed Jun 01, 2011 5:05 pm UTC

Diadem wrote:Admittedly the US tornadoes are heavier on average. But even counting heavy tornadoes the difference between the US and other countries is not as big as you'd expect. A single tornado in the US just causes enormously more damage than in Europe. And this is entirely because of Europe having better buildings.

See, it's unsupported anecdotal declarations like this that really have no place in an SB thread. Find some data.

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Re: Tornado damage

Postby broken_escalator » Wed Jun 01, 2011 5:40 pm UTC

I looked up the citation that was used for wiki claiming that the US had four times as many tornadoes as Europe. It had some interesting tables in the pdf regarding numbers of tornadoes and waterspouts in Europe:
Table 1:
Spoiler:
Table 1: Tornadoes over land, per country per year. First two data columns give the average
number based on observations, the second two give an estimate of the expected “true” number.
For the last countries in the list, only estimates by T. Meaden were available.

tornado.JPG

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Re: Tornado damage

Postby JBJ » Wed Jun 01, 2011 6:27 pm UTC

Diadem wrote:Little known fact: The Netherlands actually has the most tornadoes of any country in the world. Most people when they learn of this fact are extremely surprised. The Netherlands is not known for its tornadoes. But that is because most tornadoes here go by entirely unnoticed. The damage an F1 or F2 tornado causes is essentionally zero.

Admittedly the US tornadoes are heavier on average. But even counting heavy tornadoes the difference between the US and other countries is not as big as you'd expect. A single tornado in the US just causes enormously more damage than in Europe. And this is entirely because of Europe having better buildings.

Yes even most Dutch houses will probably get damaged in an F5 tornado. But let's not pretend all tornadoes are F5.

I'm gonna go with all Dutch houses will definitely get damaged in an EF5 tornado. Thankfully, they account for less than 0.1% of all tornadoes.

Since nearly 95% of all tornadoes are EF2 or less, comparing the 20 or so EF0-EF2 tornadoes in the Netherlands to the 1,000 or so EF0-EF2 and the 20 or so EF3-EF5 tornadoes the US receives each year is like comparing apples to jumbo jets.

On this page listing European tornado outbreaks, there are 4 outbreaks listed with a total of between 4-6 tornadoes in the last 10 years that were considered significant due to the damage they caused. The strongest was an EF3 (T5-T7 damage). Those four separate outbreaks over a period of 5 years are less intense than a single outbreak of a mid-Western outbreak than can spawn dozens of EF0-EF3's and a couple of violent tornadoes in the EF4-EF5 range. The Netherlands has 20-30 per year. The US can have 162 in just 2 days.
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Re: Tornado damage

Postby Mokele » Wed Jun 01, 2011 7:51 pm UTC

I grew up in Louisiana, where we get all of the big disasters except earthquakes (we probably get those too, but the half-mile deep layer of mud is a wonderful insulator).

Essentially, a lot of the strategy can be summed up as "build smarter, not harder". Even in Louisiana, there are high points where floodwaters usually don't reach (most of the old building in New Orleans are on the high ground), and many bayou and coastal homes are actually on stilts elevated about 1 story over the ground (cars are often parked underneath when flooding isn't an issue). And wood isn't some sort of universal flaw - I went through Hurricane Andrew in a 100-year old wood house, because it was built with damn thick wood. Interesting side-note: in Lousiana, tornadoes are especially problematic because most homes don't have basements, because the water table is 2 feet below ground level or less.

IMHO, a lot of the problems come from cutting corners - everyone wants more house for less money, so costs are trimmed by buying property in the low areas of the floodplain or using thinner walls etc. And because of the long odds, the property can pass through many owners, every one of which gets a good deal out of it until the last person gets screwed.

It *is* possible to build against natural disasters, and it happens when they're common enough. In Guam, everything's made of reinforced concrete because they get hit with so many typhoons of such strength that anything else will be destroyed in short order. I'm not sure whether there are building codes or whether everyone just realizes how stupid it is to not build in anticipation of the multiple typhoons per year, but the result is a mostly damage-proofed island.
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Re: Tornado damage

Postby KestrelLowing » Wed Jun 01, 2011 8:41 pm UTC

Mokele wrote:I grew up in Louisiana, where we get all of the big disasters except earthquakes (we probably get those too, but the half-mile deep layer of mud is a wonderful insulator).

Essentially, a lot of the strategy can be summed up as "build smarter, not harder". Even in Louisiana, there are high points where floodwaters usually don't reach (most of the old building in New Orleans are on the high ground), and many bayou and coastal homes are actually on stilts elevated about 1 story over the ground (cars are often parked underneath when flooding isn't an issue). And wood isn't some sort of universal flaw - I went through Hurricane Andrew in a 100-year old wood house, because it was built with damn thick wood. Interesting side-note: in Lousiana, tornadoes are especially problematic because most homes don't have basements, because the water table is 2 feet below ground level or less.

IMHO, a lot of the problems come from cutting corners - everyone wants more house for less money, so costs are trimmed by buying property in the low areas of the floodplain or using thinner walls etc. And because of the long odds, the property can pass through many owners, every one of which gets a good deal out of it until the last person gets screwed.

It *is* possible to build against natural disasters, and it happens when they're common enough. In Guam, everything's made of reinforced concrete because they get hit with so many typhoons of such strength that anything else will be destroyed in short order. I'm not sure whether there are building codes or whether everyone just realizes how stupid it is to not build in anticipation of the multiple typhoons per year, but the result is a mostly damage-proofed island.


Right - it really depends on where you live and how common all the issues are.

For example, if you live in the north where everyone gets tons of snow, people tend to either have stronger roofs or they tend to have methods of removing the snow fairly easily. Everyone does it because if they didn't, roofs would collapse. Everyone has the problem, the problem can be solved, and they use the solutions available to them.

In the Midwest, the only major destructive natural disasters are floods and tornadoes. No earthquakes, no tsunamis, hardly any forest fires (I don't really consider most blizzards or ice storms major - some are, but those are relatively rare). If you're not on a flood plain, you really only maybe need to worry about tornadoes, but tornadoes are different because they hit such a small percentage of the population. The house across the street can be demolished, while your roses are untouched. The risk is so small that it just doesn't make much sense to spend tons of money to make your house tornado proof, even though that's possible. If you're really worried, get some good insurance and make sure you've got a basement.

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Re: Tornado damage

Postby dethmaul » Thu Jun 02, 2011 6:48 am UTC

I second the dome home idea. That's definately what I'm going with when I build. They cost half of what a normal house costs, and they are stronger. And they're round, so even if they weren't strong, there wouldn't be a crushing snow load. And tornados go right over them.

Why don't we encourage people to build dome homes in crap areas? What's keeping these things from going mainstream besides hang-ups about what's 'different'?

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Re: Tornado damage

Postby Azrael » Thu Jun 02, 2011 1:22 pm UTC

dethmaul wrote:They cost half of what a normal house costs, and they are stronger. And they're round, so even if they weren't strong, there wouldn't be a crushing snow load.

There's a whole pile of not well supported assumptions in those two sentences.

First off: on a per-sq ft (or sq m) basis, what are you basing the cost estimates on? It wouldn't surprise me if costs significantly rose for a number of reasons: economies of scale for one, but also because existing construction, plumbing, wiring and HVAC technologies have developed to existing building methodology. Any change in technology carries a huge cost burden. Were land cheap and ample enough that all residences could be single floor (which it isn't) than in- or through- slab techniques currently available reduce this complication dramatically for plumbing and wiring. As for colder climates, HVAC challenges abound, including that concrete is a terrible insulator -- so now you're talking about having to insulate via a composite layer dome, further increasing your cost.

Also, about being round: Sure, a reinforced spherical structure can be made to be stronger (let say on a per-unit weight basis) thanks to hoop stresses. But were you to make it equally as strong (thus, saving cost) than a round roof is not uniquely adapted to shedding snow load. Compared to an entirely flat roof, yes. But the vast majority of houses in snow-load areas aren't flat roofed. There's a much more complex calculation to be done comparing the curvature of the dome to the slope of a pitched roof before you can begin to make such claims.

So ... I'm not really sure you have enough data to really make those claims at a residential level yet.

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Re: Tornado damage

Postby savanik » Thu Jun 02, 2011 3:04 pm UTC

Azrael wrote:dethmaul wrote:
They cost half of what a normal house costs, and they are stronger. And they're round, so even if they weren't strong, there wouldn't be a crushing snow load.

There's a whole pile of not well supported assumptions in those two sentences.


As far as cost estimates, YMMV. There's not a lot of data to draw on, since these houses are relatively uncommon. The actual construction is likely to be a lot cheaper, because it's essentially sprayed concrete, which is a fairly well known technique for making oddly-shaped concrete structures.

Furnishing and finishing, though, will definitely cost more. If you're willing to waste some space and have square bookshelves that don't fit well into round corners, you can get away for the standard pricing. If you want fitted furnishings, you're going to be looking at either a lot of work yourself, or some fairly pricey contractors. Likewise, electrical and plumbing - if you're willing to have exposed conduit, easy. Not a lot of residential places are happy with that, though. And speaking from experience, running conduit inside concrete and then trying to pull 16 ethernet cables through a 1/4" conduit is no fun.

The bigger problem is selling it. People don't want houses that are 'weird' or 'nontraditional', they want the comfort and familiarity of a regular shaped house. So really, a dome house is not as valuable as a normal one, simply because of the lack of demand compared with the cost of the product. That gets into a lot of economics, though.

As far as strength, one of the biggest contributions is not that the house is a dome, but is that it's monolithic - a single structure. The 'roof' is firmly attached to the 'walls'. Thus, it cannot just blow off the top of the house like your standard construction. If you look at hurricane-proofing a home, they follow that same general idea with traditional construction houses - tie down the damn roof to the walls with giant metal straps so it doesn't blow away.

All told, though, I personally think they just look cool. :) It would be neat to form a city based on the idea that 'all buildings in this area must be monolithic dome construction.'
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Re: Tornado damage

Postby dethmaul » Thu Jun 02, 2011 3:49 pm UTC

I think I remember that 15-25 bux per SF - then a bit more for customizing - is an average estimate. What does YMMV mean?

http://www.one-eleven.net/~domekits/domekitprices.htm

http://www.domehome.com/productinfo.html

http://www.monolithic.com/topics/domes

Even if you don't make it out of concrete, it's still a head and shoulder above rectangles as far as I can tell. It can take 40 feet of snow per square foot of roof, wind curves over it instead of smashing into the side, the basic construction is CHEAP. Even after all the fancy finishing, it's still under the hundred thou average for a regular home. They come in single stories to 3 story mansions, too. You can bury them if you want. Conditioning the air is cheaper, since there's no corners for pockets to form in. The wall panels can come pre-sprayed with R-40 insulation.

You can make the walls inside squared if you want. Just shape them different. There's tons of interior pics around. It's a shame some people would shrug this off and not look into it, simply because of a mental hang-up about goofy stuff. We should make a test city in Oklahoma :)

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Me321
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Re: Tornado damage

Postby Me321 » Fri Jun 03, 2011 6:23 am UTC

stevenf wrote:In the UK press it was reported that all that was left of a bank in Joplin was the concrete vault - what proportion of people have a concrete bunker to hide in in their homes?


In tornado ally, a lot.
http://en.wikipedia.org/wiki/Storm_cellar
or the newer version:
http://en.wikipedia.org/wiki/Safe_room

I would guess that about one in 5 people in Oklahoma have one of the above, we have 2x yearly tornado drills in our schools, and most buildings have a blue tornado shelter rout along with the red line on the fire evacuation map.
I learned how to read weather rader the first spring I lived in Oklahoma, and I was only 10.
The first thing I do when entering a building I have never been in before is look for the tornado shelter and the fire exits.
An e-mail I get from my University every year links to this site:
http://www.ou.edu/oupd/tornado.htm
Notice the you are here arrow :) thats 1 tornado coming within about 35 miles of any given location in the center of that map each year.

I am in favor of mobile home parks being required to have a storm shelter, and offering a permanent tax credit for installing them in homes (the temporary one after May 3rd 1999 has expired [ I think]).
http://en.wikipedia.org/wiki/1999_Oklah ... o_outbreak

Anyway the stratigy for dealing with tornados is:
Have a small hole that you can hide in while the rest of your house is moved to the next county.

As for how building stand up to tornados:
http://en.wikipedia.org/wiki/Fujita_scale
http://en.wikipedia.org/wiki/Enhanced_Fujita_Scale
http://en.wikipedia.org/wiki/Tornado_in ... and_damage

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Re: Tornado damage

Postby savanik » Fri Jun 03, 2011 9:46 pm UTC

dethmaul wrote:I think I remember that 15-25 bux per SF - then a bit more for customizing - is an average estimate. What does YMMV mean?


Your Mileage May Vary.

To put it another way - a beginner can't tell the difference between a $5 tennis racquet and a $5000 graphite-core depleted-uranium unicorn-horn-trim racquet, but a pro sure can! (I.e. you can spend as much as you want to on the high end for furnishings.)

dethmaul wrote:You can make the walls inside squared if you want. Just shape them different. There's tons of interior pics around.


True. You can. But if you have interior walls that are all square, you *will* lose some space, it's just how the geometry works. And windows are always a little interesting in this kind of structure. No way around it.

dethmaul wrote:We should make a test city in Oklahoma.


Agreed! We could get started on putting together some designs in Google Sketchup. You game?
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dethmaul
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Re: Tornado damage

Postby dethmaul » Fri Jun 03, 2011 10:29 pm UTC

Never heard of Google Sketchup, but I sure do like playing 'house', heh heh.

I'm game to try.

EDIT - You know what I thought of, looking over all that wikipedia? How come skyscrapers never get blown over by tornadoes? 100 years ago, when we were building our 'major' cities, did they KNOW they were building in quiet areas, or was it by accident? Did they research weather patterns and conclude that this certain spot would be better than that one over there, or was it just coincidence? They built there for convenience, and it just happened to be in a quiet area? Or did they see 'Los Angeles Junior' get destroyed and decided to try it again 100 miles north?
Last edited by dethmaul on Fri Jun 03, 2011 10:51 pm UTC, edited 1 time in total.

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savanik
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Re: Tornado damage

Postby savanik » Fri Jun 03, 2011 10:38 pm UTC

dethmaul wrote:Never heard of Google Sketchup, but I sure do like playing 'house', heh heh.

I'm game to try.


Check it out. It's a poor man's (free) CAD tool. Very handy. I've used it for floor plans for my gaming group before. :D
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Re: Tornado damage

Postby ++$_ » Fri Jun 03, 2011 11:09 pm UTC

dethmaul wrote:EDIT - You know what I thought of, looking over all that wikipedia? How come skyscrapers never get blown over by tornadoes?
They get pretty badly damaged by tornados, but not blown over because they are pretty well rooted to their foundations. In 2000 a tornado hit Fort Worth, TX and did severe damage to skyscrapers.

In the recent Joplin tornado, the hospital, which is something like 8 stories tall, was shifted off its foundation.

I don't think we've ever seen a collision between a modern skyscraper and an F5 tornado, but I wouldn't bet on the skyscraper. The most recent that I know of was the Great Plains Life building in Lubbock, TX, which was hit by an F5 tornado in 1970. It suffered extensive structural damage, but it remained standing and was eventually repaired.

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Re: Tornado damage

Postby Dark567 » Fri Jun 03, 2011 11:22 pm UTC

dethmaul wrote:Never heard of Google Sketchup, but I sure do like playing 'house', heh heh.

I'm game to try.

EDIT - You know what I thought of, looking over all that wikipedia? How come skyscrapers never get blown over by tornadoes? 100 years ago, when we were building our 'major' cities, did they KNOW they were building in quiet areas, or was it by accident? Did they research weather patterns and conclude that this certain spot would be better than that one over there, or was it just coincidence? They built there for convenience, and it just happened to be in a quiet area? Or did they see 'Los Angeles Junior' get destroyed and decided to try it again 100 miles north?

Basically we've never seen a f5 hit a skyscraper directly. There is nothing about St. Louis or Chicago that masked them less likely hit than the surronding area, they just haven't because tornado hits are rare.
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