is it possible to build tornado proof home?

Posted by: picard120

is it possible to build tornado proof home? - 06/12/08 11:18 PM

Is it possible to build a tornado proof/resistant home?

There are increased incidents of tornados across the midwest US and other parts of Canada too.

Is it expensive to retrofit existing home with extra re-enforcement materials?
Posted by: Shadow_oo00

Re: is it possible to build tornado proof home? - 06/13/08 12:08 AM

I don't see why not, but don't ask me how as I'm not a builder. My guess would be either brick, poured concrete walls, or earth berm or dug in, maybe even a Monolithic Dome. Key area would be the roof and making sure it is attached to the walls more securely than in a conventional built home. As far as upgrading an existing structure, I doubt you could do it without a lot of expense even if it's possible. But you could always do like I did and build a shelter in your basement if you have one. I used solid concrete blocks for the walls as well as covering the 3/4 in plywood roof with them. I got the idea and plans for it here.

http://cache.viewimages.com/xc/3060812.j...55A1E4F32AD3138

Haven't had to use it yet, hope I never do but it's there if I need it.



Here is another idea.

http://www.rd.com/images/tfhimport/2000/May00_AskHandy/May00_AskHandy_TornDam_resize2.jpg


Plans for either a storm shelter or a fallout shelter would work.
Posted by: bws48

Re: is it possible to build tornado proof home? - 06/13/08 12:14 AM

Possible is a big word. A program manager friend used to say "sure, bring money." An underground home would be my first thought as tornado proof. Also energy efficient, but that's another topic.

But on a more realistic level, I think it depends on the tornado. IMO, an F5 direct hit would flatten almost any home that could be built at a reasonable cost. The forum members in Florida would have better idea, but you can "harden" your home with various upgrades to stand up to high winds (pick a number) and minimize damage. How well those changes would stand up to a tornado is open to question.

Perhaps another idea might be to investigate how much a tornado proof "storm cellar" might cost, and what it would consist of, so you can protect your family. The house can be rebuilt: the family can't.
Posted by: LED

Re: is it possible to build tornado proof home? - 06/13/08 12:19 AM

A dome home might work.

http://static.monolithic.com/disaster_resistance/index.html

Posted by: KG2V

Re: is it possible to build tornado proof home? - 06/13/08 12:24 AM

Possible? Yeah

Every Nuke containment dome is designed to be tornado proof.

True story:

Way back when, I worked in "environmental testing" - One of the labs I used was involved in testing the doors to the containment structure. This was the scenario. An earthquake hits, and knocks down the tubine/support building, leaving the door exposed to the outside world, then an F-5 tornado hits, picking up a 60 ft electrical pole from the spares kept in the neighboring pole yard, and flings the pole small end first at 300 mph into the weakest spot of the door - the door had to survive

First - how do you design the door (not the labs problem) but esecond - how do you TEST the door design?

Answer - Build a copy of the door, and build a section of containment dome wall with the door in it in the middle of a BIG open field. Build a fairly long "blow gun" out of steel pipe that will fit a 60 ft electrical pole - wrap the pole with rags to make an air tight fit, and get a BIG High Pressure Nitrogen trailer filled with something like 10K PSI nitrogen, and blow the pole out the pipe at such a speed that the pole is in free flight at 300 mph at impact.

I didn't see the test in person, but I did get to see the high speed videos taken of the test. The "bang" was quite impressive. Oh, and the door passed

You think you can build a building that can withstand that? It's not just the 300 MPH winds you have to deal with - it's the very large objects moving 300 MPH you have to deal with
Posted by: JCWohlschlag

Re: is it possible to build tornado proof home? - 06/13/08 01:55 AM

Of course it is possible to build a tornado-resistant house. (A tornado-“proof” house is debatable, kind of like the term, bullet-“proof”.) Just Google for tornado resistant house. You’ll get results that range from dome structures to different forms of concrete homes.
Posted by: jmarkantes

Re: is it possible to build tornado proof home? - 06/13/08 02:02 AM

I know companies advertise "safe rooms". Google will bring up a bunch. They're usually a steel box, either steel frame or plate. Or they're built with insulated concrete forms (icf). Lots of good info on the net.

Jason
(Not an expert, just had to learn for a home builders website I'm working on.)
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/13/08 02:07 AM

Man oh man, that beats a chicken cannon all to hell!!!
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/13/08 02:10 AM

I am not from tornado country, and quite frankly, they scare the hell outta me. It took me forever to get over the almost daily waterspouts I saw coming at me across the Bay of Panama long ago. But I gotta think that building a tornado proof shelter in your basement might well find you trapped in said shelter by what used to be your home. If I had one of those basement things, I would make sure that A LOT of friendly folks knew about it, so they could come dig me out...
Posted by: Art_in_FL

Re: is it possible to build tornado proof home? - 06/13/08 03:08 AM

Build it below ground with a sturdy door and that is about tornado proof. Underground is good. It takes advantage of the power of dirt. Dirt is cheap, easily available in most locations and it is pretty darn hard to break. You can move it around, in which case you might need to shovel it back into place, but generally it doesn't break.

In the Philippines they built houses into the side of a mountain. Put a concrete veranda peeking out the back of the mountain. Over this they placed a thick concrete slab hung off large chains. When a hurricane approaches they disconnect the chains and allow the slab to slope down to meet the concrete floor of the veranda. this protects the glass doors and back of the house.

When the storm passes they jack the slab back into position and reconnect the chains.

Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/13/08 03:33 AM

Now this is an underground shelter that can whip any tornado...
Posted by: KG2V

Re: is it possible to build tornado proof home? - 06/13/08 05:25 AM

Originally Posted By: OldBaldGuy
Man oh man, that beats a chicken cannon all to hell!!!


Yeah - the "parts" for the test rig were still the the parking lot behind the lab. Another fun test - how do you test the valves designed to shut parts of the "primary loop" in a Nuke plant in case of a LOC accident. In that case, you would have something like a 12" pipe with water flowing through it a HUGE velocities, and the valve has to close in I forgot how many milliseconds

similar setup - big horizontal pipe with valve in the middle, a pair of "burst disks" (flat plates designed to break when under a certain pressue) downstream of the valve, a big water tank (with VERY thick walls) and the truck full of HP nitrogen again - fill pipe and tank with water, and apply high pressure nitrogen on top of the water. When the burst disk breaks (with thousands of PSI of pressure on top of the water), the water tends to flow 'rather quickly', and cuts off abruptly, as the valve slams shut. Quite a water hammer on the system, and the slug of water tends to do a LOT of damage "down range". That test was done in the Long Island Pine barrens - ripped up a LOT of scrub pine. (back when few people lived out past Coram). Now you could not do that test out there - area is all built up. You also have to worry about little things like "what happens if something breaks...."

Environmental test was probably the most interesting field I ever worked in. They give you an object to test, and a "test spec", and you had to design the mechanical, electrical, and software system to not only do the test, but prove you did, and see if the object passed or failed.

The one kind of testing I always wanted to do was "Naval Hevay weight shock", but the company I worked for didn't build anything that needed more than ""Middle weight shock", which was impressive enough. In heavy weight shock (only done by like 2 test labs in the world) your item is strapped to a barge (of a certain design) and they start setting off what are basically depth charges closer and closer to the barge. Your item does NOT have to keep working - the test is to make sure that parts of your item don't break off and go flying around. Seems that during WWII, they found out that more sailors were killed by parts flying off of gear, often 100s of ft from where an explosion was, than actually the explosion
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/13/08 01:38 PM

"...Quite a water hammer on the system..."

I'll bet there was!

"...setting off what are basically depth charges..."

That could be fun! Hey Blast, you reading this???
Posted by: KG2V

Re: is it possible to build tornado proof home? - 06/13/08 01:58 PM

some links for your viewing pleasure

http://www.hitestlabs.com/hw.html

http://www.ntscorp.com/pdf/locations/Rustburg.pdf

Like I said - it was an "interesting" job - trying to break things my company was building - but only in certain ways, and giving them ideas HOW to both design and test things so they wouldn't break, despite my trying
Posted by: James_Van_Artsdalen

Re: is it possible to build tornado proof home? - 06/13/08 02:30 PM

There is "-proof", "practical" and "cost-effective". A "-proof" house won't have any windows or doors that don't resemble bank-vault doors...

I think what's usually considered "cost-effective" in areas where basements are impractical is a to make a kitchen pantry or walk-in closet with reinforced concrete walls and ceiling, firmly attached to the foundation (usually with rebar into the foundation), and a steel door.

Brick is entirely non-structural as far as I know: I think all it adds is flying debris.
Posted by: Nishnabotna

Re: is it possible to build tornado proof home? - 06/13/08 03:55 PM

The only structure I would trust to be proof would be an underground home, similar to a cellar. As mentioned earlier it is not only the winds you have to worry about, but the flying debris - perhaps more so.
However, the design of my Lustron is pretty good. One Lustron was known to take a direct hit from F5, and while the glass and roof panels were gone afterwards, the structure was still standing with even the ceiling panels still in place.
All steel construction FTW.
http://en.wikipedia.org/wiki/Lustron
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/13/08 06:27 PM

You could get together with a bunch of rich friends and buy one of these...
Posted by: DesertFox

Re: is it possible to build tornado proof home? - 06/13/08 07:00 PM

Bucminster Fuller was the master of doing more with less.

http://en.wikipedia.org/wiki/Geodesic_dome
Posted by: KG2V

Re: is it possible to build tornado proof home? - 06/13/08 10:19 PM

Bucky Fuller story,
My wife grew up attending a UU congregation on Long Island. Fuller came to speek, and at the time my wife was like 10 YO. He went on and on about saving energy, and saving gas (era of the 1973 gas crisis) Mary raises her hand, and being a young girl, he calls on her, and she points out the window and asks "then why are you driving a Rolls Royce?"

Posted by: LaLine

Re: is it possible to build tornado proof home? - 06/13/08 10:24 PM

Those who talked about the debris being more of a problem then the high winds reminded me of a poem I read recently. I typed it up for your enjoyment...

Problems with Hurricanes - Vincent Hernandez Cruz (from his book "Red Beans")

A campesino looked at the air
And told me:
With hurricanes it's not the wind
or the noise or the water.
I'll tell you he said:
it's the mangoes, avocadoes
Green plaintains and bananas
flying into town like projectiles.

How would your family
feel if they had to tell
The generations that you
got killed by a flying
Banana.

Death by drowning has honor
If the wind picked you up
and slammed you
Against a mountain boulder
This would not carry shame
But
to suffer a mango smashing
Your skull
or a plantain hitting your
Temple at 70 miles per hour
is the ultimate disgrace.

The campesino takes off his hat--
As a sign of respect
towards the fury of the wind
And says:
Don't worry about the noise
Don't worry about the water
Don't worry about the wind--

If you are going out
beware of mangoes
And all such beautiful
sweet things.
Posted by: Jeanette_Isabelle

Re: is it possible to build tornado proof home? - 06/13/08 10:32 PM

Wouldn't that depend on the model of the car? Seriously, though there is no such thing as a fuel-efficient Rolls Royce, some are better than others.

Jeanette Isabelle
Posted by: Art_in_FL

Re: is it possible to build tornado proof home? - 06/13/08 11:51 PM

Originally Posted By: OldBaldGuy
Now this is an underground shelter that can whip any tornado...


That it would.

Long ago I read a piece on Cheyenne Mountain. Seems that the mountain was pretty much obsolete before it was completed. The USSR detonated a 100 MT device and had the lift capacity and accuracy to get several to the mountain. The mountain itself would survive, in a somewhat attenuated form, but the initial burst of radiation from any of those warheads would kill everyone inside.

Assuming anyone survived the radiation they would be buried under a hundred feet of mixed semi-vitrified radioactive slag that is pushing 1000F. Where anyone inside gets their air and has sufficient air conditioning to keep from being cooked remains to be seen.

Assuming they live long enough to dig their way out any survivors find themselves in the middle of a radioactive zone twenty miles across. And probably a nation on the other side just slightly more attractive.

Standard orders were that after the initial attack they would hike out and report to their chain of command for reassignment. Right.

As more than one person observed a lot of nuclear handmaidens had an implicit wish to play the high note in a fatal one act play. On the up side they would be going out with a bang. And be one of the first to know about any major event.

But against a tornado. Outstanding.

As one concrete man said - " I guarantee three things about the slab I pour: It will crack, it won't blow away and nobody will steal it".

Concrete is an excellent material for tornado resistance. Combined with the power of dirt you could make it the basis of a home that could resist any tornado. Or the near miss of a moderate sized nuclear weapon.
Posted by: climberslacker

Re: is it possible to build tornado proof home? - 06/13/08 11:55 PM

yeah, concrete has been proven oven thousands of years, literally, it has been around since Roman times, that is much older then many of the materials that we use today...
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/14/08 12:52 AM

"...Standard orders were that after the initial attack they would hike out and report to their chain of command for reassignment..."

Our Uncle Sammy believes that you have to have a plan for everything...
Posted by: Art_in_FL

Re: is it possible to build tornado proof home? - 06/14/08 07:11 PM

Originally Posted By: OldBaldGuy
"...Standard orders were that after the initial attack they would hike out and report to their chain of command for reassignment..."

Our Uncle Sammy believes that you have to have a plan for everything...


Pretty much.

I mean, were you expecting the PTB to give it to them square:

1) Upon getting launch code expedite the launching of missiles.
2) Launch missiles at designated targets.
3) Spread legs, bend over sharply, kiss ass goodbye. A Cuban cigar, a small flask of Tennessee sipping whiskey and a tape of Handel's Messiah have been provided for your entertainment while you wait.

That would be very thoughtful. And so very unlike how the military thinks. To the end the military engages in cognitive dissonance and makes believe some of these situations are survivable.

On the other hand. A guy who operated one of the Nike Hercules bases told me a long time ago told me that one of the saving graces in any war, even a nuclear war, is that if you think the US military is screwed up you don't know jack about other nations.

One estimate was that somewhere between 2% and 7% of US warheads in the 70s were expected to fail to operate for various reasons. Talking to defectors out of the USSR, Russian union for the youngsters, some estimates were about 10 of the Russian missiles would fail to launch, 30% of their warheads launched would fail to detonate correctly. And almost half of their warheads would fail to meet targeting specifications.

Forget those hopeful fallout maps. Come full scale war nobody knows where the warheads will fall and how many will go off. Particularly seeing as that Russia has had to cut military expenditures. they claim their strategic forces are unaffected but there are reports that maintenance and upkeep are not being done.

Of course warheads not reliably going off where they are aimed is a mixed blessing. Gross inaccuracies mean your retreat in that mountain valley safely upwind of all the targets might have a 100kt warhead fall on it. Aiming for the military base 300 miles away they might still get you, which would really suck.

Also warhead errors tend to be delays. Which mean that those highly efficient air bursts that don't drop much fallout could become ground bursts that are less effective as strike weapons but much more efficient at creating huge plumes of fallout. Even a warhead that fails to detonate isn't necessarily a good thing. The warheads come in a several times the speed of sound. If they hit the ground their extremely long-lived radioactive contents splatter. Creating a permanent dead zone several times as large as a football field.

It would be my luck to build a super-duper bomb shelter and have a warhead, off track and defective, land directly on top without exploding. Fallout degrades rapidly. That stuff, not so much. It might be a very well equipped shelter but I think it is going to come up short of the years I need to wait to get out. This would also suck.

In fact a lot of aspects of nuclear war suck. Which might be why the DoD optimistically tells the missilemen to report to chain of command after a nuclear attack on their base. One way of dealing with the mega-suck is to ignore it.

But I still thing the Cuban, libation and tunes are a good idea. If you have to go. Go out with style.
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/14/08 07:18 PM

Anyone visiting the Tucson, AZ, area should take the time to visit the Pima Air Museum Titan II facility. Getting a close up look at one of those big boys, watching a simulated launch, brings back the old Cold War fears in a hurry...

Link
Posted by: Raspy

Re: is it possible to build tornado proof home? - 06/15/08 04:18 AM

The Fema book.
Posted by: sodak

Re: is it possible to build tornado proof home? - 06/15/08 02:00 PM

Having been in Cheyenne Mountain, it is a very interesting design.

But unless it's underground, I seriously doubt that you can make a tornado proof structure. F5's are pretty unbelievable, I've seen asphalt literally peeled off the road. I don't place a lot of confidence in concrete, it would have to be steel reinforced, and even then, I'd be surprised if it weren't blasted through.
Posted by: James_Van_Artsdalen

Re: is it possible to build tornado proof home? - 06/15/08 03:30 PM

Texas Tech's Wind Science and Engineering Research Center does work in this area, and it is of greater interest to them than some DHS bureaucrat: I believe test structures of theirs have had "unscheduled testing" by tornadoes in the past.

PS. As for unexploded warheads: it's the short-lived isotopes that tend to be the problem more than long-lived isotopes since there's more energy emitted per second. Pu-239 is the main problem in a warhead and it has a half-live of ~ 20,000 years. Assuming it doesn't embed itself in something that acts as a moderator it shouldn't be that hard to clean up...

A more realistic problem than an unexploded nuclear warhead in the backyard is if some idiot decides to put a nuclear reactor in low-earth-orbit again and then has an uncontrolled re-entry long after criticality, something like Cosmos 954 in 1978. Neither the Russians nor Americans do that any more but others have the capability and might be tempted to try it. Not much to do but stay clear of anything that looks like debris and wait for clean-up crews to clear the area...
Posted by: OldBaldGuy

Re: is it possible to build tornado proof home? - 06/15/08 06:01 PM

"...shouldn't be that hard to clean up..."

How would simple folk like me know what to clean up, how to do it, and would we have the means to actually do the cleanup? This is assuming a really bad scenerio, where there was little or no government support. I know basically zip about that kinda stuff, other than it is supposed to make you glow at night.
Posted by: AROTC

Re: is it possible to build tornado proof home? - 06/16/08 11:39 AM

Plutonium is an alpha emitter, which means it will only harm you if particles are inhaled, ingested or embedded in you. Alpha radiation only travels about an inch and can be stopped by paper or skin. Gamma radiation is the bad stuff, it can pass through several feet of concrete shielding and kill you after only a few minutes of exposure to high levels. While I don't know what else they might put in a bomb to make it more efficient, nothing can be very radioactive because otherwise you wouldn't have a bomb after a short period of time.

A fizzle is possible, where the bomb almost but not quite makes it to a nuclear blast. This would produce a lot of radiation and radioactive material. But a full out misfire wouldn't rain much that was very dangerous around. And it might just go ahead and bury itself which would solve to problem pretty completely.
Posted by: MoBOB

Re: is it possible to build tornado proof home? - 06/16/08 05:02 PM

I second the Monolithic Dome solution. I have researched these things and visited their facility twice in Texas. When I am in a position to build I will be going this route. FEMA's highest protection category is "near-absolute" and these things have earned that rating. I encourage you to do the research on them.

Standard Disclaimer: No connections whatsoever; just sold on the idea.
Posted by: cajun_kw

Re: is it possible to build tornado proof home? - 06/16/08 09:12 PM


From Web Search of the Periodic Table ....
"Plutonium-239 is one of the three fissile materials used for the production of nuclear weapons and in some nuclear reactors as a source of energy. The other fissile materials are uranium-235 and uranium-233. Plutonium-239 is virtually non-existent in nature. It is made by bombarding uranium-238 with neutrons in a nuclear reactor. Uranium-238 is present in quantity in most reactor fuel; hence plutonium-239 is continuously made in these reactors. Since plutonium-239 can itself be split by neutrons to release energy, plutonium-239 provides a portion of the energy generation in a nuclear reactor."

Fissile material left over from an exploded nuclear device creates quite the mess ...and its contamination and very small particles that are very radioactive that can cause the most damage to humans. You don't have to be able to "see it" for it to hurt you.

Any shelter designed as bomb shelter should be adequate to handle a tornado. Though all the designs I ever looked at were below ground. That said ...and as stated before...with adequate funds ...you could build an above ground structure from re-inforced concrete and steel that would weather a tornado ...but again ... it would or coudn't have windows unless they were able to be sealed with something akin to blast doors or seriously strong shutters. Which could be done ...but again ... bring your checkbook.
I've seen storm shelters incorporated into home designs that are marketed as "safe rooms" ...most are re-inforced concrete and/or serious steel that are left standing after hurricanes and tornados tore the house down around it. But most are fairly small like maybe 8 x 8 at most. They won't stand up to a bomb blast but will weather a natural disaster. Though they'd be small. Taking that concept further you could build the basement as if it were a large storm shelter ... have a large space that could survive the storm ....your "basement roof would be the house subfloor...but you'd have to rebuild your house.
To make any "normal" looking house survive it would need to be largely re-inforced concrete with enough "lipstick" on the facade to make it look "normal" ....but its gonna be hard to seal the openings (doors/windows) in a way that doesn't make it look sinister...and it will cost a lot of $$$.
But the bigger it was, the more it would cost ... so clearly something under or around 1000 sq ft, single story, simple design... would be a more cost-effective target goal than your 3000 sq ft yuppie mini-mansion.
NO design could protect you if you weren't in it though ...and sealing yourself up in your habitat every night presents more issues to content with.
Posted by: wildman800

Re: is it possible to build tornado proof home? - 06/16/08 09:29 PM

There are many designs out there for underground homes and semi-bermed homes.

I just saw, in Oklahoma, where this family has taken an old steel tank (5,000 gals???), turned it on its side, cut in a doorway, and has buried it as a tornado shelter. It looked like it could hold between 10 and 20 persons comfortably. It is buried into the bluff created by the roadway being cut through a hill and they are facing the sides of the bluff with natural stone, on each side of the shelter entrance.

Yes, I've been on the road for the last five days but that is another nightmare,,,uh, I mean,,,,,another story!!!!!
Posted by: James_Van_Artsdalen

Re: is it possible to build tornado proof home? - 06/16/08 10:52 PM

Originally Posted By: OldBaldGuy

How would simple folk like me know what to clean up, how to do it, and would we have the means to actually do the cleanup?

Well, cleanup needs to be done by guys who have at least geiger counters and know what to do. In a repeat of the reactor re-entry scenario there will be lots of aerial surveys (you can find hot spots from airplanes and determine what isotopes are involved) followed by vans running around to pick up debris.

For civilians the important thing is to report suspicious metallic debris, mark it with a sign (skull & bones with arrow pointing at it) and maybe organize a neighborhood watch until it's removed to make sure kids and pets don't go play with it.

If there is no government help and won't be ... you won't know what it is or how dangerous it is. I'm not sure. Here is a site with plans for a do-it-yourself radiation meter, and lots of other chatter about about nuclear strike survival things.

My comment "shouldn't be hard to clean up" meant that properly-equipped teams should be able to find the contaminated spots and remove them.
Posted by: Art_in_FL

Re: is it possible to build tornado proof home? - 06/17/08 01:14 AM

Originally Posted By: OldBaldGuy
"...shouldn't be that hard to clean up..."

How would simple folk like me know what to clean up, how to do it, and would we have the means to actually do the cleanup? This is assuming a really bad scenerio, where there was little or no government support. I know basically zip about that kinda stuff, other than it is supposed to make you glow at night.


As I understand it cleanup in that case isn't very complicated. Detect the perimeter of the contaminated area, mark and calculate the acceptable exposure limit. This will set the amount of time a person can work. Dosimeters still have to be used to confirm estimations and exposures. Then you dig a hole.

If the contamination is small and on the surface you scoop up the contaminated earth and drop it into the hole you created and cover with sufficient dirt to act as a shield.

If the area is larger or deeply contaminated you take the dirt you pulled out of the hole and pile it on top of the contaminated area. Again, forming an effective shield. the decision pivots on which method most reduces worker exposure and creation of dust which might spread contamination on the wind. Water spray, sometimes with a detergent, or foam have been used to keep the dust down.

This protects people from the radiation and dust. To keep your shield from blowing away or eroding you lay down membrane and cover with clean dirt planted with grass. Or you pour concrete. Something to slow erosion.

The membrane also keeps rainwater from leaching the radioactive dross into the groundwater.
Posted by: Spiritwalker

Re: is it possible to build tornado proof home? - 06/17/08 04:37 PM

Cheyenne Mountain they ain't but I seem to recall reading about a couple of log homes that took direct hits from tornadoes and only lost their windows and roofs. Not tornado "proof" but better than having to rebuild from the foundation.
Posted by: Art_in_FL

Re: is it possible to build tornado proof home? - 06/17/08 10:18 PM

Originally Posted By: Spiritwalker
Cheyenne Mountain they ain't but I seem to recall reading about a couple of log homes that took direct hits from tornadoes and only lost their windows and roofs. Not tornado "proof" but better than having to rebuild from the foundation.


That would depend on the log home, most are not sufficiently 'unitized' mechanically and stay together largely because of the weight of the parts, and exactly how direct you mean by "direct hit". On the other hand if you were building a log home it would be possible to drill down through the stacks of logs and to install steel rods running from a poured foundation to the roof structure. These make the entire structure act as a single piece and transfer uplift loads down to the foundation.

But then again similar unitizing details are even easier to install on conventional construction.

Easier still with poured concrete or CMUs. Rebar and surface bonding work really well at holding things together.