I’d just like to bring this up for discussion as I’d like to learn more about the subject from all those of you in the know. But first a link… (it goes to the weather channel)
http://link.brightcove.com/services/link/bcpid823425597/bclid877032950/bctid1608865363
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Cheap Tools at MyToolbox.net
See some of my work at TedsCarpentry.com
Replies
Concrete dome.
Cloudhidden is your man.
=0)
Although even a concrete dome is going to sustain -some- damage.
For instance, blown out windows...
Buried, or partially buried would be best. Let's get VaTom in here as well.
=0)
Politics: the blind insulting the blind.
Click here for access to the Woodshed Tavern
an underground bunker....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
Simpson truss ties from the roof to the top plates with foam wall sheathing stapled on 8" oc. That's MI's solution. Bob's next test date: 12/10/07Edited 6/16/2008 10:11 am by Jim_Allen
Edited 6/16/2008 10:11 am by Jim_Allen
guarenteed to last in an f1minus 1?<G>
Now,now. That's not what Tom calls his house.
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
ever see that bunker on Eureka....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
No, didn't find it.
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
ya had to see it for it to make sense...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
For perspective:
318 mph, highest measured tornado.
nuclear burst - 750 kT, that yields, at 2.1 miles altitude, an equivalent wind speed of 318 mph, overpressure = 13.2 psi for a flat roof (multiply by drag coefficient for dome reduces the burden).
flat Roof loading = 1900 psf
I agree with Luka--you need something that won't offer much resistance to the winds and that will not come apart in low pressure. I figure if a containment building for a nuclear reactor will resist explosions from inside, and they are made out of reinforced concrete, a similar product would work with low pressure outside and it would work for high pressure if a tornado misses it by a bit. (Of course, a containment building is probably built pretty darn "stout" compared to your everyday house--are most people going to want to spend the money on materials and engineering?)
I also agree that buried or partially buried would be best. My feeling is that while it would look ugly, something on the order of a huge steel culvert, covered with reinforced concrete and buried to half its diameter and would be pretty good. Dome probably better, but more expensive. Weak points will be windows, of course, and those are sort of nice to have--maybe have metal shutters that close over windows.
i saw a cross section of a containment building cut open for display at a nuclear plants visitor center. pretty cool, they had lots of display and information and such, small museum type thing.
i don't remember how thick it was on the containment building, but there was so much rebar in that thing i was wondering how they got the concrete in there.
not only that but all of the rebar was welded, it wasn't just tied together with wire, every connection and place where the 47 million pieces intersected it was welded.
talk about overkill, they continued to beat that dead horse for months.
As a structural engineer in the nuclear business I can tell you that you should see the inside of the building! The containment structure inside the concrete dome is 2+ inch thick steel plate and more concrete.
And it's not overkill... it's just very, very, very, very, very, very, very, very unlikely that you'll need that kind of strength during an event. It's one of the things that makes nuclear generating stations so safe. During the Cherynobl accident, the top of the nuclear containment dome actually blew off, but that was due to so many different factors. Not the least of which was a design that is not used in the US.
believe me, as a refuel rigger i have seen the inside of them, on a couple of outages. i have been involved with rigging and reassembling the head on top and repairs under the drywell.
its been only about 15 mos since i was last badged.
can ya believe that, unescorted access to nuclear facilities. they just let me go bopping around in there wherever i want!
No, actually, I can't believe that. Which sites have you been at since you were badged? You're sure they didn't just carry over your clearance from another site in the past year? I can't believe all the guys with machne guns would just let you walk on site without a badge.
Generally, no one is allowed on site unless they have been cleared and approved for some level of badge. Being inside containment is another thing entirely and requires psych evaluations and special training. But I would be really surprised that any plant would let workers on site without some minimum clearance and a record of behavior.
But then again rigger's can be some crazy folk. Maybe they make an exception for them.
didja read the post?
i said i was badged, for "unescorted access"
i was just joking about the bopping though, and i wont discuss specifics as i have had "safeguard training"
that psych test was tough let me tell you. they must have asked me over 25 times in over 25 different ways if i had ever thought about killing myself.
i had never even thought of until they asked me so many times.
Ah...missed the unescorted part. Yeah. They ask some truly bizarre questions. I liked the ones that asked about my head feeling tight or if my body felt like it was the wrong size sometimes.
no problem, so tell me what are you working on? where do you think the next nuclear plant will be in the US?
i would love to see several of them built , we are real close to being able to recycle the waste to the point of reducing a 55 gal drum to the size of a beer can, which from what i understand they can do now but there are some nasty side effects, but they are close to doing it without producing the nasty stuff.
i have only worked on old plants, and from what i hear they are now very profitable. i would love to see this country lead the way in power. energy is the future.
Man, we could start another thread on this topic by itself.
I'm working on stuff in China, Taiwan, Japan, Brazil, Georgia, South Carolina, New Jersey, California and France.
At least three new nuclear plants in the US will begin site construction in the next year. Estimates are that somewhere between 20-50 domestic nuke plants will start construction in the next 30 years.
The south seems to be soaking up all of the new plants. Northeners don't/can't/won't build new power plants to save their life. Regardless of whether they are nuclear plants or coal. Or refining and processing plants for other fuels.
It's kind of sad. One nuke plant creates about 5000 jobs in the immediate vicinity of the plant. 800 of those are high tech jobs. 400 of those jobs are skilled craft jobs. Those are typical numbers. To be sure, there are other concerns that arise when you look at introducing a nuclear plant into an area. Not the least of which is the extra 16-20 gallons per day per person water consumption the nuke plant adds to the demand in the area. That is a big deal in Georgia where power plant requrements for water are might begin to compete with agriculture needs and both are requiring more conservation from the locals. But I believe that the benefits outweigh the negatives.
-Chris
Northeners don't/can't/won't build new power plants to save their life. Regardless of whether they are nuclear plants or coal.
I'm in IL, does that count as northerners? Our electric utility is constructing a new coal fired plant.
http://www.cwlp.com/electric_division/generation/new_plant_under_construction1.htm
We've got a nuke plant about 45 mins away, but it isn't new.
jt8
"A little 'enthusiasm' and all problems seems small!"
Worked for CWLP 43 years ago (did some of the surveying for the HV line down Dirksen).
Sometimes wonder if I'd still be there if Spfld had anything else to offer <G>
Have often thought CWLP could build even bigger with a larger lake (hear that is in the works) and cut city taxes to near zero by selling power to nimbys nearby.
The city alderman are not that smart. They can't see any further than the end of their nose. So the second lake has been in the works for 30+ years (and there is talk about selling off the thousands of acres they purchased for it) but probably won't get a kick in the butt until we have a goodly drought...hope we still have the land to put one on then.
The water pump facility is about to fall down, but no one wants to vote for the $$ to pay for the replacement. Meanwhile the price of materials has gone waay up, so it will cost more to do it now.
CWLP wanted to build a much larger electric plant, but the aldermen wouldn't go for it. Sierra Club pressured CWLP into purhcasing "X" amount of wind power. The aldermen fought it tooth and nail. Cost a fortune in delays. In the end, they purchased the wind power anyway...and sold it for a profit. But you still hear people whine about having to buy wind power. Idiots! You sold it for a PROFIT. The CWLP officials were all for buying it in the first place, but the aldermen didn't want outside folks telling them what to do.
It is almost enough to make you want to run for alderman to try and get stuff done, but I'm sure I wouldn't last, because I'd have to tell them what I thought of them at some point. ;)
jt8
"A little 'enthusiasm' and all problems seems small!"
I would put Illinois in the mid-West. But maybe that's a matter of perception. From what I've read, they have tried to start three new coal fired plants in IL, including one really new concept carbon sequestration model. But that got turned away too. This past April there was bill to allow construction of new nuclear plants in IL again. Did that pass?
we could start another thread on this topic by itself.
Probably ought to--I'd like to ask on whether anybody has found a way to build pebble-bed in the US for power production.Occupational hazard of my occupation not being around (sorry Bubba)
Met a guy yesterday who used to work for Admiral Rickover. Talk about a guy who put his stamp on U.S. nuclear issues.++++++++++++++++++
What goes up must come down unless it gets into a stable orbit.
I also agree that buried or partially buried would be best. My feeling is that while it would look ugly, something on the order of a huge steel culvert, covered with reinforced concrete and buried to half its diameter and would be pretty good.@@@Earth sheltered might be the way to go...This sounds like a SAM - Steel Arch Magazine. The Navy designed these - often built in groups of three - concrete floor, half cylinder of corrugated steel sections, concrete end walls and lots of dirt fill between and overhead.I used to show the class the test film on these - 100,000 # of HE in the center mag. Bang. Door goes west, roof unfolds and rises on the fireball. Damage to adjacent magazines - well, they cracked the slab a bit.The ToolBear
"I am still learning." Goya
i would be willing to bet that a standard frame house with a few modifications and very careful attention to detail would do quite well.
you would of course have to have plenty of simpson connectors carefully attached, and i would spec 5/8 ply for all sheathing, including roof. i would also spec construction adhesive everywhere, and then spray foam on all exterior sheathing to further glue and firm structure.
i would also spec a hip roof detail with no overhang, flush to the walls as a sealed exterior unit, and then i would hang sacraficial overhangs, something that looked like a dutch hip when you were done, but those sections would be like blow out walls in a hurricane zone, designed to let go after subjected to X amount of wind force.
then i would add some heck for stout storm shutters, with a good blocking/backup integrated in the framing, so that if the storm is coming you close shutters and screw/secure.
i bet all of that could be done without adding much cost to a standard frame house. it wouldn't withstand a direct hit if the storm was strong enough, but it is impractical to go around building nuke containment structures to live in.
standard frame house with a few modifications
Think it would take a little beefier structure in addition to simply adding 'ties'
Maybe Ron could add in a note on the amount of modifications that would be needed to a standard truss to go from 20psf to 300 psf??
Grew up in tornado country, Mom's house was just 2 blocks away from a tornado core 3 years ago.
When a kid, before we went into the basement, we would open the windows, as there has been previous tornados where the windows in the neighborhood had blown OUTWARDs. After one near miss, all the drapes were outside the house, Mom said she was going to leave the windows closed the next time and take the chance on the windows blowing out vs having a mess to clean and the floors being covered with water.
The best estimates for core pressures in a F5 is a sudden drop of about 2 psi, or close to 300# sq ft. (like a 750kT nuke 11 miles away!). A roof designed for 20 psf, with or without Simpson or other ties, just would not last (BTW, just in case <G> my own house is NON-standard - built with the 2x10 roof rafters set on a 1x4s at the sides of the wall framing studs, bolted connections)
At 300 psf, most windows will be blown out and standard prehung experior doors partially blown out of the framing. Solid oak doors whould withstand if good hinges and non-standard buttplates and hardware.
BTW, a good method of getting 'barn wood' for cabinets off an old timber frame barn is to set off 1/2 stick of dynamite inside - leaves the frame, strips all the siding without too many splits.
i said lots more than just adding ties,
no overhangs
glued and spray foamed for better glueing of 5/8 ply to all exterioir, roof, walls, rim, etc
i am not an engineer, but have heard over and over how foam "stiffens" up a structure.
i also think a conventional framed hip roof is stronger/more resistant to wind forces than trusses.
my main point was that properly detailed with just a few changes over standard and little added cost a structure would do much better!
"Maybe Ron could add in a note on the amount of modifications that would be needed to a standard truss to go from 20psf to 300 psf??"
Piece of cake. The question is - Could you afford it ???
the roof trusses wouldn't be that big of a deal. But how would you tie them to a wall so as to deal with that kind of force? How would you tie the walls to the floor system, and the floor to the foundation? Those things would be your limiting criteria.
Inflation is when the buck doesn't stop anywhere.
Grew up in tornado country, Mom's house was just 2 blocks away from a tornado core 3 years ago.
Two F2's. Cut right across town. Hard to believe that no one was killed!jt8
"A little 'enthusiasm' and all problems seems small!"
would be willing to bet that a standard frame house with a few modifications and very careful attention to detail would do quite well.
That winds up being a yes and a no.
Yes, you can build frame houses to a 200-225mph wind spec for not that much more in time and labor (and attention to detail).
The "No" for tornados is not the windspeed or over/under pressure--the damage is in the debris.
Also, whe you get to F4 & F5, the winds are not straight line to the house. Perversely they are only the forward speed of the storm cell, around 30 mph. However, that funnel edge has wind ripping along at 250-300mph tangential to the house. That's an angle that'll strip trim, light fixtures and such. F4 & up can be a kilometer across on the ground, too. It can be hard to even save the frame at that point.
The Jerrel tornado was a sobering experience for folks in the shelter biz. The tornado sheltering research folk at Tech, up in Lubbock, are still checking and double checking their recommendations. Which involves a great deal of ciphering with the meteorolgists along with reviewing the first & second responder's reports from afterwards.
But, you have identified a critical issue. Keeping the frame together for as long as possible is what decreases damage in actual storms. Keeping roofs attached, porches from flying loose (or disassembling into less harmful parts, a la safety glass).Occupational hazard of my occupation not being around (sorry Bubba)
I appreciate this thread, as I am repairing a house and rebuilding a garage after an F2 tornado went by two and a half weeks ago.
A lot of damage from flying debris. Two car attached garage was another story. Numerous problems with construction added to damage of it.
First - it was tied to the 6" block top course by short anchor bolts that were only in the top row. And, placed approx. 8' apart. The next row is 8" block that has the concrete floor sitting on top of it. Almost all of the top row of block were pulled off.
Second - the truss against the two story section of main house was just pinned for most of it's length. Framing nails through truss and 7/16" OSB and maybe into studs. Only the ends of from 4' to about 8' were tied to the rest of the roof with 7/16" OSB roof sheathing.
Third - trusses were nailed with three, yes 3, toe nails. NO Simpsons, even though those had been spec'ed in the plans. (Read - no inspections required in this area.)
Homeowner has determined from damage that tornado lifted the roof off one corner of the garage, then blew the walls out. One section of one wall has yet to be found. This then allowed the roof trusses to end up on their vehicles.
And, three sections of one of the garage doors have not yet been found. That agrees with another post here that said the overhead doors are a weak link in a garage structure.
The tornado hit in the night, about 1:30 am. The couple were awakened when their bedroom window blew OUT, not in. It was the only room where anyone was at the time. And, it was the only window that blew out. In all the rest of the windows the glass shattered to the inside.
I was their third call later that day. Call one - his father, who is a contractor in Cleveland, to help them button things up. Call two - insurance company. Call three - me. We had built a garage two and a half years earlier that was just 50' from the one destroyed. One window broken, one piece of siding missing (top piece of vinyl), and a few cap shingles missing. Rest of damage was from flying debris. And, yes, we built it much different. So, who else would they call?
"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
Well, now you know what not to do. :)
Not that you wouldn't have know that already, but just had to say it. I guess it's not so much making a structure tornado proof as it's making a structure tornado resistant. Of course, the concrete dome is probably the most resistant, flollowed closely by the underground dwelling. But I think most of us prefer tradition rectangular structures with lot's of windows.
I seems the one you're rebuiilding was originally built to withstand the most severe nice, sunny day. --------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
It would be interesting to see some stats on total $ value of wind damage vs the strength of the storm. I'd bet that 80% of the damage (outside of hurricane country) occurs with straight-line winds or tornados of F3 or less, simply because they're much more common. With these blown debris is less of an issue, and it boils down more to keeping the roof on and keeping the siding from peeling off.Of course, the more severe storms are deadlier, so survivability is an issue, in addition to cost-effectively minimizing damage.
It is an ironic habit of human beings to run faster when we have lost our way. --Rollo May
It would be interesting to see some stats on total $ value of wind damage vs the strength of the storm.
Probably the insurance industry has some of that data. I don't know an elegant way to get that data, but it would be where I'd look first. (That, and actuarial data can be already sorted into constant dollars for better analysis.)
I'd bet that 80% of the damage (outside of hurricane country) occurs with straight-line winds or tornadoes of F3 or less,
That jibes with my recollection. Also, recall that a significant portion of wind damage in hurricanes is from tornadoes formed in the storm bands (there's a lot of shear in the forward motion, which will rotate into horizontal and vertical vortexes).Occupational hazard of my occupation not being around (sorry Bubba)
"i would be willing to bet that a standard frame house with a few modifications and very careful attention to detail would do quite well.you would of course have to have plenty of simpson connectors carefully attached, and i would spec 5/8 ply for all sheathing, including roof. i would also spec construction adhesive everywhere, and then spray foam on all exterior sheathing to further glue and firm structure."Not if it is a direct hit. Read this:http://www.coastalcontractor.net/cgi-bin/article.pl?id=144
the title says it all, hurricane proofing won't make it tornado proof, but its a start.
i am all for structural concrete construction like VATom does, and i understand that type of constrcution appraises higher than standard frame construction.
and i even hear VATom saying its not that expensive. all good, but like i said before with just a little thicker plywood, a slight change in design and construction, and careful attention to detail a house would do a lot better.
i have built stuctural concrete, you need some serious equipment, wall jacks aint gonna get it. it might not be that expensive, but i would like to see some sq ft costs to compare.
A lot of new homes don't have ANY plywood. Just 1/2" foam board with vinyl siding over that.
Pathetic.
I remember some project specified steel rods from foundation to top plates. I did a quick web search and came up with a couple of products that are designed for this:
http://www.coxlumber.com/huribolt.html
http://www.tdi.state.tx.us/wind/prod/fa/fa14.pdf
I would assume that cables could also be designed to work.
yep
pathetic it is.
it might not be that expensive, but i would like to see some sq ft costs to compare.
OK, so long as you understand the pitfalls. Notoriously difficult to mean much. Confine it to the shell of a certain size...
Cloud once took large exception when I posted I'd built the cheapest underground house I could. I used more than twice the concrete his domes get. But we both came in low $20's/sq ft for the same-size shell. Somewhat higher today.
In his case that was assuming local labor available to do the job, which is often not the case. Imported skill labor costs more.
For cast-in-place, my last house was me (the skill guy) and 2 college kids who'd never worked construction before. An extra guy, or preferably 2, on pour days. It's the low-skill labor that offsets my larger concrete use, along with my higher form cost. Did you read the page on my place about the crane operator's shock about the low cost of the steel roof? From a guy who routinely sets wood trusses.
I've got a lot more man-hours in formwork than the subdivision guys here, but come out OK with cheap labor. Not as low-cost as the subdivision guys, but like I mentioned about the appraisal... It works. Not because concrete appraises higher than stick-built, it doesn't here. The high appraisal had nothing to do with the type of construction. Only the low cost did.
Think about it. The reason this is common commercial construction isn't high cost. Otherwise they'd be doing something else.
I'm currently helping an Atlanta guy with his house. He found me after he'd already had his engineering and plan completed. Very similar to my place. Serendipity? Nope, just paying attention to what commercial construction is there. He's a CPA. Who also thinks that a no-maintenance house is desirable.
Just what "serious equipment" do you think I need? I bought a vibrator and a concrete chute. Then we need a pile of 2x4's, CDX plywood. Bunch of snap ties and wedges. A used rebar cutter/bender came on board for the second house. The original worm-drive is still doing fine. I don't own a laser, or portable compressor/nail gun, no need.
As my houses are buried, something to move dirt is required. I own, but rental works fine. Either way, very inexpensive compared to roofing. And provides the passive heating/cooling system.
Hope that answered your questions. Most certainly underground isn't for everybody, but it's inexpensive. Here's a sample of my first effort, nearly 20 yrs ago, obviously not OSHA-compliant.
PAHS works. Bury it.
the serious equipment i was referring to was a crane for setting and removing forms, like i said i have done a lot of structural concrete and much prefer to build panels and set them rather than wrestling with sheets of ply and cowbells. even a small boomtruck would do but still costs a lot more than wall jacks for raising a heavy wall when you are framing.
then there is the concrete pump for each pour, again you said you had a chute, and it could be done that way but i much prefer a pump to place concrete. yes i am raising the cost of construction here but i think the lower stress on pour day is well worth it.
then there is the equipment to move dirt, which you would have some of that with any conventional building.
i remember your post about your crane guy commenting on the low cost of the steel for your roof, and wonder about that too, i work with steel all the time and keep hearing about how expensive it is, i am at a loss.
if you can build shell for anywhere near $20 per sq ft that you can actually bury i can't understand why every house isn't built that way.
segundo,
I watched a new poured wall foundation go in recently and the time it took to set and remove the forms was massively longer than the same time it would take to build that same foundation with ICF's.. In addition to massively expensive forms and big expensive equipment to haul those forms around as well as lift and remove those forms far exceed the cost of ICF's. meanwhile a poured wall is not as strong as ICF wall because of the differance in rebar..
In addition a poured wall does not have an easy way to attach sheetrock or anything else short of powder shot. Far more expensive attachment..
I am quite sure that if you were to use as much rebar as in a bridge that would work better than no rebar. So I do not know where you get the idea that ICF walls are stronger. ICF walls are just poured concrete inside of insulation. When I was in Mexico I worked on a project that used concrete on the outside of foam.
gb93433
ICF's use Rebar in them.. the thickness of the walls and the strength of the walls can be set by the thickness of the walls.. Minimum I know of is 6 inches. Maximum commonly available is 15 inches..
You take that much reinforced concrete and tell me that a stick framed house is stronger I'll demand to see the testing.. SIP's have been tested!
They are rated at wind speeds up to 200 MPH. They have up to a 4 hour fire rating.
Take a sledge hammer to To a stick framed house and very quickly the wall will be splintered and laying on the ground.. Take that same sledge hammer to a cement block wall and in a few blows the joints will give up and down it will tumble.. take that same sledge hammer to a 15 inch rebar enforced ICF wall and IF you are lucky and really strong Hours later you might have punched a hole thru it..
On top of that concrete by itself is a lousy insulator. ICF's correct that problem.. and provide a easy way to make the rest of the house.
That is my point as well. That is the reason why I cannot see that ICFs are any better or any worse than a poured wall. In essence they are a poured wall with insulation on the outside.
gb93433
Well from that point yes you are correct in that ICF is the same as a poured wall of the same thickness. Well maybe a tiny bit stronger in that the foam will absorb some impact damage that a poured wall won't..
But even in southern locations where your main energy consumption is cooling and not heating, the insulation of the form is desireable.. In addition it's extremely difficult to attach sheet rock etc. to poured concrete walls whereas with ICF forms you have a strip every six inches to screw sheetrock to..
I've watched crews set up& strip forms for poured walls and they take nearly the same total time as it does to set up ICF forms.. The differance is that you don't need mego dollar expensive cranes to lift 2 pounds of a form into place.. Thus the net cost should be lower than the cost of putting up and stripping forms..
I have seen the reverse of ICF's where the walls were insulated on the inside and concrete on the outside and then tilted up. One picture I saw was done by Lithko. If I remember right it was 130 feet high. I have often thought that one could do tilt up construction and then texture the concrete. A few months ago I saw a program on TV that described the same thing I mentioned and they said that the tornado damage was very small. Their promotion was that damage due to very high winds would be minimal because of the concrete exterior. If I remember right it had been tested at 400 mph.I would think that if concrete could stop a bullet it would be able to stop tornado damage.
gb93433
Tilt ups are standard commercial construction.. usually around here they have the insulation in the middle with concrete on either side of prestressed panels. Textured outside walls are relatively standard.
Years ago I built an ICF house and the time it took was enormous because the strips on the foam blocks were thin and did not hold very well. Recently I spoke with the Nudura salesman and saw the product. The blocks are 18" high by 8 feet long, The strips on the outside are much thicker too. So if one were to sue that product it seems like things would go along faster and smoother.
> So if one were to sue that product it seems like things would go along faster and smoother.I've observed that things rarely go faster and smoother when you sue. ;)
It is an ironic habit of human beings to run faster when we have lost our way. --Rollo May
Okay spelling cop. I should have used the word "used." Sometimes my fingers do not move as fast as my brain. It is partly because of the work over the years that my fingers do not straighten out and cannot move so easily.
gb93433
Well with that sort of experiance I can understand why you aren't a big fan.. My experiance was just the opposite. It went together so easy that once I started it my sister-in-law with absolutely no construction experiances at all finished it for me ( I was bed ridden and in extreme pain and my drug slurred 15 minute instructions were apparently enough)
My second experiance was when I did the front bow and by that time I was so cocky I went completely off the page and it still came out perfect!
Well, yeah, one can clearly spend (waste) as much money as you like on any type of construction. What I said was that I can and do build inexpensively.
The subdivision guys here beat my prices using their small cranes and panels. That's not more expensive, considerably cheaper or they wouldn't do it. I greatly dislike pumping, but it only added $1500 to the cost of my client house (the one with the great appraisal). If you wanted, you could also include the cost of massage therapy for pour days.
Appears your main problem is: "i work with steel all the time and keep hearing about how expensive it is, i am at a loss." Ever consider pricing it and comparing the total cost (labor and material) to conventional construction? That's how I came to build with these materials, it's cheaper.
Not only the crane guy, but the steel delivery driver was extremely interested in my purchase. He delivers steel all day, every day, had never seen such steel used residentially (40' span). Neither guy had a clue, clearly not uncommon. When I mentioned the bill for the delivered steel, both were astounded at how cheap. Then I mentioned that if we didn't have a large earth load to support, I could have eliminated over half that steel. Like you, they'd both heard how expensive steel was.
You probably also think $100/yd concrete is incredibly expensive? I don't. Your problem is seemingly a lack of perspective. Take a good look at the whole picture, completed cost.
Sure, I'd prefer that steel hadn't risen 50% in a short time a couple years ago, or that I could still get $70 concrete, but that doesn't make this construction prohibitive. Think about it: why is this common commercial construction? Or better yet, price it out.
Why more aren't building this way is that they are doing exactly the same thing you've done. "Hearing about how expensive it is", rather than actually exploring the possibility. Which is what the Atlanta CPA did, on his own. He's subbing everything. Neither he nor I knew any better, so we explored. Sometimes you get a pleasant surprise.
Other times, not. Cast-in-place T beams were an example of that. When I went back to the engineer to ask if I'd made some calculation errors, he explained that the incredibly high cost I saw was why it rarely happens.
I've got no illusions, what I did could be done cheaper, or immensely more expensively. With your preconceptions, I wouldn't be overly surprised if you did find higher cost. It's amazing, some of the quotes I've gotten. But nobody varies much on the cost of the materials, only the labor to place. Man-hours I understand. Then you apply a dollar figure.
The major wall contractor here wanted $8500 labor to place $1500 worth of wall rebar. Does that sound reasonable to you? This was during our planning discussions, when he'd started with some very bad assumptions, but reasonable pricing. He didn't get any work.
Lastly, you wondered why every house isn't built this way. I've got a passive cooling/heating system. Zero maintenance, zero operating cost, inexpensive installation. Appearance can be just about anything you desire. Why haven't you got one? The book was written in 1983.
You live in a climate that needs dehumidification. My heat pump water heater's running now. You have one? They're hardly new. Payback is surprisingly short. My payback happened 5 yrs ago. Just did my first maintenance, a new Taco circulator cartridge. Not my passive ideal, but sure works well with it's free by-product: cool dry air. Are they commonplace? Not here.
PAHS works. Bury it.
Tom, I've said it before and I'm saying it again: You need to give us a Photo Gallery thread detailing a PAHS going in. Like a Smith thread with play-by-play as each element is being completed. That way people can see it with the current prices and headaches.jt8
"A little 'enthusiasm' and all problems seems small!"
Yes, John. If the crew happens this summer, or I get organized enough to find one. You know I'm no GC, or have any aspirations along that line.
You are correct, I'm behind on current pricing. Did check out current xps cost recently and was pleasantly surprised it had changed little (truckload volume). Assuming we do finally get a Ga building permit, I'll know a lot more from that relatively quick all-subbed construction. Pretty much my place, with a basement.
My heat calculations are not recognized by the state of Ga, only a PE's. Unfortunately, the plan approver isn't allowed any discretion, and PEs there don't know how. Still waiting to hear what happened with a Seattle PE who does.
And I'm still in contact with the one Cloud PAHS project (Kansas). Land title problems delay for the past year. No heat calcs necessary there.
Hey! Here's a thought. Why don't you do a thread on one? <VBG>PAHS works. Bury it.
Did you have a thread with pics of yours somewhere? I vaguely seem to remember seeing them, but can't track them down with the search feature.
The short answer is "no". I'm not that organized, tacked pieces onto other threads. Like this one.
There're some errors, but most comprehensive is the page put up to surprise me, that one of our BT handlers thought was my web page and put in my profile. Which you might have seen: http://paccs.fugadeideas.org/tom/index.shtml
I've learned a lot since then. PAHS works. Bury it.
Ok, that is probably where I saw it. Just a few questions remain.How did you seal the roof, and are there any penetrations through it? I can see at least a stove pipe and at least one pvc coming out the sides.Is there insulation under the floor as well, or is it in direct ground contact? From the PAHS i've seen, it should be in contact with the ground.Would it be feasible to use ICF's for the front facing wall, and standard pour for the ground contact ones to maximize heat storage?What would you do different?Think that's about it.
Haven't I put everybody to sleep yet? Apt questions.
Roof penetrations strike me as more trouble than they're worth. Sharp eye! That's the woodstove pipe. Occasionally gets used, coming out the front wall. Gets cleaned every couple or 3 years. You saw the stove in the inside. The sole vent's out a side wall, where the air system comes in.
Roof isn't sealed. I wasted money on bentonite water-proofing here. Didn't do that again. Great stuff, but unnecessary. Now, just 6 mil poly near the concrete, then dirt, then the umbrella (with 3 layers of 6 mil poly around the insulation layers), then the top dirt. It's the umbrella that does all the work. Scrap carpet to protect the poly from tears and burrowing critters.
My client insisted on a standard foundation drain. Just like here, never had a drop come out. I plugged mine, expect he's done the same.
You're right, no insulation under the floor. We don't have enough earth contact for best performance as it is. Cloud had a very hard time understanding why his beloved radiant floors and PAHS don't mix. Not just the philosophic differences.
ICFs would work for the exposed walls. Not quite as good thermally as insulation only on the outside, but I doubt anybody'd notice. ICFs I recommend to anybody who's unwilling to do formwork. Not in my future.
You've got a good understanding of how it works. Incredibly simple, eh?
Our next place, out of the ground (barely), has a large garage, guest suite, indoor 2 lane lap pool, sound-isolated office, utility room. Will get twice the overhead dirt under the umbrella. Other than that, pretty much like here, but faces west to sunsets over the Blue Ridge. It too will be over-glazed, under earth-contacted, but performance will be improved.
I'm recycling an active solar system to heat the pool. As it'll be a considerably more expensive place, there'll be easy retrofit of the things upscale buyers here expect. Like central heat and ac. Not intending to relocate, but ...
Tested on the second house, we are in fact over-insulated on our exposed walls. Better to do heat calculations first, saves money. Not a lot, but no reason to waste.
DW originally thought I was nuts, but as it was only "temporary" she'd move into anything to avoid another winter in that drafty farm house we'd rented. After a couple of years here, she wanted almost exactly the same thing, but with the above added features. I can't adequately stress the benefits of a fresh air system. She suffers when she travels. Anywhere.
The Atlanta guy is planning to adjust air pressure, to counteract atmospheric changes. Seems his DW is extremely susceptible.
May add earth tubes to our next place, depending on how the Atlanta experiment works out. Mold's the fear. I'd love to switch to a passive air/dehumidification system. While I just acquired another heat pump water heater. I prefer to stock a spare of most everything.
PAHS works. Bury it.
Good point about misconceptions.
Every carp should build or buy a house and live in it for two years and do it again. Eventually the moves should clear the mortgage. The common rule of thumb is 5 moves and you own it . Do they do it ? Nope they dont. I dont know why.
Tim
I guess that's a 20% return on each house.Is that with the carpenter doing all the labor, on his own time, essentially for free?
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Im sorry, I didt explain it .
I dont really know where it came from. Its not from me .
Here carpenters build houses or do remodeling . Theres no other work for them.
Carpenters build their own houses here. Carp goes to the bank and borrows the money from the bank .
They can live off the loan just like a job . They build 5 houses a year , theirs can be one of them.
"Is that with the carpenter doing all the labor, on his own time, essentially for free?"
Jon I havent built a house in a few years but the last one I built I didnt get paid but other people did most of the work. I just hired a crew of carps that work from the back of their truck for hire. Not what I call contractors as they work for them half the time . Although I didnt get paid I was 30 percent off appraisel . So I could have drawn 10 percent and been left with 20 percent . I didnt need it .
Ive heard it all my life and seen it done as my dad had a lumber yard I worked in. Carps would do this over and over as part of their living . Its what my dad always did. I moved 6 times in grade school . The theory always seemed to be do what you do and let others do what they do and help except if they dont want any help . Around here is was common place for the different trades to build their own houses . Not just carps . I guess Im really talking about subs in a country setting .
So yea you act as a contractor on your own house but you are a sub really. You do what you do normally and over see the job. Theres 30 percent profit in that. Contractors want cost plus 20 percent and they get paid . Their time isnt in that 20 percent . Its profit. Be the same for a contractor to do one as many have done . Ive worked for a bunch of subs through the years being a sub myself and hired a bunch of them.
Ive had two brothers in the trades as well. We were the crew at one time with dad as contractor. He worked too of course . Its funny we helped each other but we all picked different specialties. Weve all helped each other build our own houses from the ground up but we all got paid .
So from dad doing it as a kid and when we had the lumber yard we built and sold lumber it was being done by us and lots of people I waited on were doing it. Then through out the years working as a sub too , I learned the 5 rule . Do 5 and you own it never having to pay for it in payments.
Step up in time to the last 17 years in my life , Ive bought them cheaper than I can build . Major reason I dont build rentals as a rule . Repos have been cheaper . The major difference with repos is you get what they will let you have not what your tastes are building your own. You never get what you would have chosen but they can be just as nice or more for the money than you would have built . Well, maybe not you . <G> Ive never had an opportunity to buy an underground house really. Well not finished . Ive saw two that were unfinished but I didnt really want them. One had the walls up and another had the roof on but thats it. Pretty rough and I didnt really have any idea as how to finish them not knowing how they roughed them in. I guess that was misconception too as I didnt spend a lot of time thinking about it . They were very very cheap and sat there forever not sold . Guess everyone had the misconception.
Tim
Edited 6/18/2008 7:10 pm by Mooney
"'Carp goes to the bank and borrows the money from the bank . They can live off the loan just like a job . They build 5 houses a year , theirs can be one of them. "" Can you elaborate on that?
Do you mean the carp borrows enough money all at once to build five houses?
Or borrows enough for one at a time and sells four that he has built and has as a result made enough profit to build his own.
They can't get your Goat if you don't tell them where it is hidden.
Where I live carpenters build houses for a living .
They built specs and lived off the loan money. Their own loans . They build for others as well. They do build around 5 houses per year. They work by the hour , as subs , for homeowners and contractors as well.
Tradesmen in general built specs as well . I know an electrician that builds two per year spec.
Different subject ;
A tradesmen can build specs they live in till they sell. After 5 houses they can own one outright from the profits. 20 percent per house savings. Live in them till they sell but hopefully live in them two years and take advantage of the tax savings. They can own one that way. Pretty easy plan if all is well.
Tim
Got it , same is done here. I just misunderstood your post.
Thank you.
They can't get your Goat if you don't tell them where it is hidden.
Hey! Here's a thought. Why don't you do a thread on one?
My conventional project house sucks up plenty of my time, I don't need another one at the moment. Besides, I'm more of an earth sheltered, super-insulated frame of mind. I need that additional nudge to go PAHS.
And you don't need to be a GC to give us a good thread on a new one.
jt8
"A little 'enthusiasm' and all problems seems small!"
OK OK I'm in.
You have convinced me.
all about the part where you don't like pumping, and the massage therapy thing?
i was talking about the boom pump that is fairly easy to place the concrete with if you have a decent operator. should be no need for a massage.
as far as labor involved with placing of steel and forms lots of experience with both so no problem there for me.
i am assuming you prefer structural steel to the cast in place T beams? did i read and understand that part correctly?
did i mention that i am an extensively certified welder, and can make anything you want out of steel in just about any location/position. might come in handy in this type of build.
i need to get the book written in 1983. is it titled "passive cooling and heating"?
LOL... Sorry, I really do try not to proselytize. There's enough of that around here already. You pushed a button.
I've pumped 5 times, easy placement for sure, but I get inferior concrete for that premium price. The last time (forever, I hope) it was supervised by the guy in charge of the Va fleet of pumpers. He'd been in the business forever. Was determined to show me that there was no reason to dislike pumping. Drove well over an hour to give me his free labor.
Good that he wasn't around when we stripped the forms. Hard to say what I might have done. It wasn't pretty. My client, who had insisted on pumping, apologized to me. It was obvious to him too, and he was there on that pour day. Several here at BT have tried to convince me that pumping is fine. I'm sure others are happy, just not my experience.
Instead, I bought a crane ($1k, well double that before it was ready to use) , to lift concrete buckets. I've also used an all-terrain forklift with a bucket, which worked fine. Very little more effort than boom-pumping. Gravity works surprisingly well. <G>
Cast-in-place T beams would have been incredibly expensive, prohibitive. Whereas my steel was surprisingly cheap. I learned to weld (a little) on my roof. Welded a washer, on top of the decking, to the bar joists.
Won't do that again. The client house was minimal welding, just the ends of the bar joists to the embedded plates. Decking got shot. A buddy describes my efforts as gorilla welds, strong and ugly. I'll remember you, obviously didn't know much of your background. There's obviously a whole lot I don't know about construction.
"Passive Annual Heat Storage" by John Hait, ISBN 0-915207-00-1. Far as I know, out of print. Available as an e book, below. There's a major concrete guy in Oregon who's beseeched me to publish my take on PAHS (passive annual heat storage). About all I did was separate the architecture from the heating/cooling. Hait built a dome.
Here's an excerpt: http://www.earthshelters.com/Ch_1.html
Seemed obvious to me, but confusing Hait's architecture with PAHS is common. Then, after building my place, I went into heat loss/gain calculations, which Hait doesn't. Lets you apply PAHS to vastly varying climates. This is where I've probably contributed the most. Well, and by exploring alternative constructions.
For instance, there's a guy in San Jose who shares my interest in earth-formed thin-shell concrete. The thin-shell community, Cloud included, thinks we're way around the bend. What they miss is that PAHS requires a huge amount of dirt, earth-forming simply uses it twice. Take a loader with 3 yd bucket and it doesn't take long to move a pile. One of them lives here. And I get away from needing that skilled spray crew.
This is a synthesis of Felix Candela (a fabulous Mexican architect/engineer of 50 yrs ago), Paolo Soleri (an Arizona architect famous for designing unbuilt cities), and Hait's PAHS.
More interesting, appears I have a small crew for this summer here. Grad students at the local U., one's a Lakota. Extremely interested in better reservation housing. You never know where something like that might lead. Got my attention, I've seen western reservation housing.
I've been approached by "eco villages" to build a spec house. Don't think so. If I wanted to do that, I've got land here. And a real interesting rough plan.
We all have to decide how we want to live (and in what). My ego's insufficient to try to change the world. Y'all're on your own. I spent the remainder of this morning picking cherries. Very satisfyingly unlucrative.
Thanks for posting.
PAHS works. Bury it.
Just 0.02$ from another engineer.
There are plan specs that were designed by the Engineering department at Texas Tech that are freely available through FEMA. Check out the link below.
http://www.fema.gov/news/newsrelease.fema?id=9643
I've been involved with natural hazard mitigation and protective engineering against winds and projectiles. You really have to take into account the local area and building materials too. You also have to consider wind born missiles, which is an enitrely different matter from figuring out how to keep a roof on. A good missile type to consider in the mid-west is a 200 MPH 8' 2x4. In Florida, near some high rise apartments or condos, I'd be worried about falling AC units AND laterally oriented missiles. The requirements to prevent missle intrusion, keep the roof on and generally protect the occupants vary greatly in those two cases.
Either way, a safe room, or safe structures to resist that sort of damage, require special detailing. Kudos to you guys for thinking about it. Most people don't.
Best Wishes,
Chris
Either way, a safe room, or safe structures to resist that sort of damage, require special detailing. Kudos to you guys for thinking about it. Most people don't.
I didn't either. A safe room was planned for our "real" house. This place was designed as a future furniture shop. A maintenance-free one.
Large glass expanse makes for nice living. But not so good for either high winds or heating/cooling. We'll do it again.
Thanks for the link.PAHS works. Bury it.
No problem!
As for the nice glass expanse, there are safe ways to do it in tornado/hurricane/earthquake country. But they're mostly all site dependent.
The skinny Portland house in the June FHB is a good example. The window wall is oriented towards another house close by with closed off angles of attack that would make it very difficult for a missile to penetrate into the building envelope but still admits lots of light.
-Chris
abbysdad.
Most tornados come from the south west around here.. I'm located in a sheltered area where to get to my home the Tornado must drop down steeply which uses energy and as a result will disapate force.. Dense thick follage (trees, shrubs) also disappate energy and provide a barrier of sorts.
So location does become important. Positioning is also important.. But nothing beats mass.
Stone and concrete offer the ideal protection for high wind speed damage..
Absolutely. Mass and thick walls are best. Just sayin' there are options if you're in that country and still want a window wall.
Perhaps eventually some professors will start thinking about how to prevent or disapate tornados. You have warm, moist air coming up from the Gulf and dry cold air coming from the Rockies. The warm air wants to rise and the dry air wants to sink; they mix and you get your tornados.
Now Kansas has been scientically been proven to be flatter than a pancake. [A micrometer traverse of a real Aunt Jemima compared to a topographical map of the Flat Earth State.] The winds of those two air masses are not in themselves that great. But when they combine, they can reach +300? Perhaps Kansas could use some hills?
My own approach would be steel beam construction with 1/8" thick steel outer shell. But right now I'm more concerned that the Iowa floods may spread to San Diego. After all, we are downhill from there.
Wood has tremendous tension strength. However it has a direction known as grain. Steel is omnidirectional. The weakness of wood is in the connections. We tend to build everything with flat planes. This is good for situating furniture in corners. Animals build roundish nests.
An approach would be to build like a wooden boat, perhaps upside down. Round portholes. No square stress points. Curved keels and ribs -- perhaps cross laminated. [Home Depot already sells curved 2 X 4s.] 3-dimensional concave or bowl shaped pieces of plywood.
These are just some ramblings I'm tossing out.
~Peter
pm22
ICF's are a simple way to build.. well proven and established construction technique and would be massively less expensive than your steel home.. In addition it is suitable to do-it-yourselfers as well as poorly trained crews typical of a lot of home construction.. The walls in ICF homes are rated by themselves up to 200 MPH and will easily absorb any fly debris impact without pentration.
Building in the round would add a tremendous amount of cost to construction. In addition virtually eliminate the cost advantage of mass production.
Steel is required to be prepared in factories or shops prior to hauling to the jobsite because the massive equipment needed to Cut, punch, and modify are too heavy to be hauled into the field and used there.. Steel prefabrication adds dramatically to the costs of construction. (as does the raw cost of materials.
Square windows are simpler and less expensive to build. Round windows weren't required in aircraft untill they started to pressurize the aircraft hull repeatedly and the corner stress points started to fail..
Totally agree with the ICF comments. Don't mess with something that works so well.
Another question though. Most of the damage that occurs in homes that are not in the direct path of a tornado are damaged by missiles and pressure equalization. Missiles you can defend against, but build a tight weather proof house and once the windows or garage blows out you've lost the battle against the wind. Has anyone come up with a system or details to open a house envelope safely so that the structure can equalize pressure with the exterior and prevent blow out?
Outside of that, my only recommendation in tornado country is to build a safe room and make sure that the garage is not attached to the house.
abbysdad,
Well one of the myths about tornados is that things blow off or out from wind pressure. If you've ever looked at aerodynamics you'll understand that a window can be blown out without over pressuring a roof or "exploding" a house.. (That's only part of it so please don't take this alone)
Please realize that the pressure is similar around the house. The walls must be strong enough to withstand wind pressure and they can't do that without the aide of the roof. But if the roof remains on the walls, even stick built walls are remarkably strong.. Assuming the roof remains on the amount of lift generated by the house is dependant on a variety of things such as the roof pitch.. the more vertical the roof the less lift is created.. Shallow pitch roofs have more lift than steep pitch roofs..
A window or windows when blown out cannot really create enough pressure to remove the roof.. The volume of air entering the house thru a window is insufficent to blow off the roof. Think of an air hose aimed in a car window. Sure there is 125PSI at the end of the hose but that air quickly expands to fill the area inside the car untill air pressure is a tiny increase over outside air pressure.. The same thing occurs when a window is blown out.. In addition the pressure of air long before it will remove a roof or "explode" the walls will blow out windows on the opposite side of the house making a path for air pressurization equalization..
What actaully happens in a tornado is lift caused by the same forces that lift airplanes off the ground lift the roof and the house itself is frequently retained only by whatever fastens it to the ground. Once the roof is removed the walls are going to fall down or blow off..
Projectile protection comes from strong walls.. Brick or stone veneer provide a lot of protection over vinyl siding. Real stone is superior to fake stone.. In the event of a tornado put as much protection between you and the direction of the tornado (lacking a basement) Even interior sheetrock walls will provide added protection over nothing.
"Well one of the myths about tornados is that things blow off or out from wind pressure. If you've ever looked at aerodynamics you'll understand that a window can be blown out without over pressuring a roof or "exploding" a house.. (That's only part of it so please don't take this alone)"
That's correct. The wind pressure doesn't cause things to blow out or in. The internal pressure in the house acts on the inside of the window as the wind speed picks up and creates a region of lower pressure on the outside of the window. The window blows out to equalize pressure across the window. That's why a window can blow out due to high winds.
"A window or windows when blown out cannot really create enough pressure to remove the roof.. The volume of air entering the house thru a window is insufficent to blow off the roof. Think of an air hose aimed in a car window. Sure there is 125PSI at the end of the hose but that air quickly expands to fill the area inside the car untill air pressure is a tiny increase over outside air pressure.. The same thing occurs when a window is blown out.. In addition the pressure of air long before it will remove a roof or "explode" the walls will blow out windows on the opposite side of the house making a path for air pressurization equalization.."
That's also mostly correct. The worry from a window or wall blowing in is a pressure wave, or rarifaction, through a house that starts in a place like the garage and then goes through a smaller opening (like the door into the kitchen) which slows the wave down and increases the air pressure, which blows out the inside of the house and generally causes a lot of mess. This sort of pressure wave can cause significant damage to a home and can blow off a roof. In the case of a window, it might just give the wind a corner to grab onto. In the case of a garage door buckling, it can cause severe damage to a house. That's why in high wind country I tend to recommend seperate, or very well detailed, garages.
"What actaully happens in a tornado is lift caused by the same forces that lift airplanes off the ground lift the roof and the house itself is frequently retained only by whatever fastens it to the ground. Once the roof is removed the walls are going to fall down or blow off.."
Also correct. But the importance of a wing that gives positive lift is that the air moving under the wing is going slower than the air going over the wing so the structure is lifted into the air. Give the wind a chance to get into an attic space and the air inside will be moving much slower than the air outside. Which will cause your house to try and find OZ if it is not attached to a foundation properly. What I was curious about is a simple concept that is used in fluid systems all the time: a pressure relief valve or a diffusing chamber. If the pressure outside the home ever became dangerously low, or if the windspeed picked up enough that roof damage was likely, why couldn't someone design a channel that would equalize flow through the attic (or the house, whatever), and pressure in the house, so that blow outs and lift off never happened? Alternatively, how about ground effects? Cars seek to have the opposite effect; wind pushing them down into the ground. Couldn't a roof be designed with that concept in mind? Figuring this out would just take some imagination and access to a wind tunnel and some models.
I agree with the ICF comments. They are a wonderful tool and build efficient, safe homes. But even with ICF I'd still think about a steel plate reinforced safe room as per the FEMA recommendations and based on past experience with tornados.
Chris
"I agree with the ICF comments. They are a wonderful tool and build efficient, safe homes. But even with ICF I'd still think about a steel plate reinforced safe room as per the FEMA recommendations and based on past experience with tornados. " Saw a show recently (Smash Lab) where they coated the inside and outside of a one story hollow block wall room with Rino liner. It survived a massive car bomb without collapsing. I would think that would be cheaper than the steel plate.
http://blogs.discovery.com/smash_lab/2007/12/beginning-with.html
To protect windows, someone mentioned window shutters. There are several outfits, in Florida in particular, who manufacture roll down aluminum shutters that are supposed to be able to protect windows during severe hurricanes. I am thinking about installing them on my future house to protect against wildfire, assuming the cost is manageable when I start to build. Another item designed to protect windows from impact is impact resistant films. Some of these are designed for DIY. I remember some time back viewing a video of a two by four shot against a window to which film had been applied and it was surprisingly strong. Unfortunately, a check at the time showed that the film was surprisingly expensive - not as expensive as repairing the damage of a shattered window in a storm perhaps. It seemed at the time that if one was doing new construction, it probably would have been about the same price to install impact resistant windows initially rather than do regular windows and install the film. I don't recall what the light transmission is for the impact resistant film, but I assume it is noticeable.
I think the original question didn't involve cost.
If you have seen pictures of houses falling apart -- as in falling over a landslide, you might notice that is breaks apart at the seams. That is, the roof remains more or less intact. And the walls. They are held together by the plywood siding. So my idea was to somehow eliminate these week points.
FEMA now has a bunch of slightly used formaldehyde infested trailers. Perhaps these could be deployed around the countryside as bogus decoy trailer parks. It is a known statistical veritude that trailers attract tornados.
~Peter
Sorry, I didn't mean to post that until after I had sincerely thanked you for the knowledge you have passed, and the lifting of the veil. I can see the light!
said the blind carpenter, who picked up the hammer and saw.
It's all a waste of time and money. I worked in a neighborhood that took a direct hit from tornados. I was in the sub the next day putting temp roofs on. Across the street, there was a house completely gone: nothing was left except the chimney. Right next door, there was a ranch house with only a shingle missing and one broken window. Those house were all framed with no sill plates, no foundation anchors and no rafter hold downs of any kind. In those days, the houses were framed with the trusses toenailed to the plates. Bob's next test date: 12/10/07
Ive worked a lot of T damage . Its like you say . One house destroyed and next door nothing but normally there is somthing you might not notice passing. Ive seen hoods pretty well destroyed too and the next street over hardly anythng .
It takes a tornado making a direct hit to the ground and staying there to cause univeral damage . Hardly ever happens .
This spring our news reported that we had an empty rent house in the eye and it was reportedly on the ground right there according to their mapping. We drove out there and found no damage anywhere in the area. 2 miles from there and not mentioned it took 3 homes to the foundation.
Tim
Have a brochure from a urethane spray foam company that shows a church standing in the middle of total tornado devestation. The difference was, it was spray foamed. Apparently it does add significant strength. I like your idea about sacrificial eaves,makes total sense. I also like the idea of 5/8 ply, maybe add a few extra ringshanks ,every 4". What about ICF's with a couple of flying buttresses, I just love those 2 words.
I just got home from work and wow, 29 replies! I'm glad I brought this up!
Reading through all this, four distinct points seem to stand out.
A) Flying debri is at least as damaging as the tornado itself.
B) The wind near the core can blow right through foam sheathing covered with vinyl siding (you'd never get me to buy one of those pieces of...)
C) The negative pressure within the core is like a giant shop vac going around sucking up roofs, thus allowing the wind to blow the walls down.
D) Little short of a nuclear test facility comes anywher near tornado proof, but houses could be built to stand a much better chance at surviving.
Oh, and a fifth item, E) An underground shelter ain't a bad idea.
There's a lot of good info here, and some pretty good links too. That article reinvent linked to is pretty good (http://www.coastalcontractor.net/cgi-bin/article.pl?id=144), very insightful.
So I guess ICF construction with plenty of rebar, SIP panels or reinforced concrete for the roof, tied all the way to a deep foundation, steel roll-up window and door shutters, and/or really thick safety glass windows would provide optimal protection.
However, even stick framed construction could be designed better through use of tie rods from the top plate to the foundation, the trusses bolted and/or Simpson tied to the top plate, and steel shutters on all the windows. Add spray foam insulation for even more bonding strength and for extra rigidity.
Did I miss anythign?--------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
Oh, and break-away eves and anything else that could catch the wind.--------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
TedW.
Actaully solid over hangs will act like "flaps" in high speed wind and cause it to stall.. however as overhangs are built today they are weak add on's (you need a little course in aerodynamics to understand the concept)..
Overhangs as they are built today are weak. When the birds mouth is cut it weakens the strength of the rafter. If you look at my over hangs you could lift trucks with them.
Yeah, the car tossed by the tornado ... through your roof sitting on your foam form concrete house and all your belongings sucked out to the land of Oz. :)
I'm buying stock in Simpson Strong Tie. :)
Ted W.
Not only can you build to withstand tornado's/hurricanes I've done it!
First, the pratical aspects.. the British Misquito plane of WW2 was mostly wood and it would approach 500 mph in a dive. Wood that basically was glued together at 500 MPH! Oh sure, there were small brads used to hold the wood together while the glue dried but once dried the glue did the work..
The real secret to withstanding a tornado is keeping the roof on.. once the roof is off the walls have little to hold them erect and topple easily.
Thus the connection between roof and top plate are critical. The average toe nailed connection can only take 208 pounds before failure.. mutiply that times the number of connections and then figure out wind lift and you'll have a number where the roof will come off.. Toe nails basically won't withstand much wind force over 80MPH.
Simpson connection increase that streght dramatically starting at an H4 at 547 pounds and going up thru an H7 at 2,726 pounds. The real strength is gained through the use of properly installed lag bolts.. where the strength depends more on the woods resistance to failure than the connection itself.. even an improperly installed lag bolt will hold a rafter on at 2783 pounds..
With a proper pilot hole and shank hole predrilled a 3/8 lag could hold in excess of 4000 pounds.. with hardwood rather than soft woods those numbers can exceed 5000 pounds and in my case actaully exceed 8000 pounds (white oak timbers and 1/2 lag's properly installed) In addition instead of a single point connection each rafter tail has three 1/2 x 12 hardened 18/8 stainless steel lag bolts. Two vertically and one horizontally. Together they provide me with more than 20,000 pounds of resistance per timber! (considerably more than the 208 pounds of my neighbors roof).. <grin>
There is even a stronger (and simpler) way to achieve the same effect. Build with ICF's. Those walls are capable of withstanding 200mph wind speed by themselves.. add a good rafter top/plate connection and you have a simple basic house capable of withstanding a full F5 tornado or the most violent Hurricane..
In another place and another time, I had an engineering professor that was fascinated with tornadoes. I had him for Statics but he talked about designing houses that could withstand a tornado quite frequently. The key as he put it was preventing wind intrusion, if the wind is able to get in a little bit it will take a wall or the roof and then the structure is going down. Connecting the roof to the foundation is critical. He said it would be ideal to have no overhangs and use metal strapping bolted to every rafter and then run down the wall and bolted to the foundation to prevent uplift of the roof. You need wind and impact rated windows and door that are connected properly. The garage door is often a big problem. It is a large expanse of fairly weak metal, he said single doors were a little better than double doors but often a garage door is the point of first failure that leads to the failure of the rest of the structure.Your second problem is impact resistance. In tornadoes you have a lot of debris that will puncture a house and then allow wind in. I saw with my own eyes where a F4 had crossed I-44 a license plate had been shoved through a metal guardrail like the rail had become butter temporarily. When you have a tree or your neighbor's car hit your house at 150 mph what kind of strapping, sheeting, or foam insulation you have doesn't matter a lick.If I were building a house to survive a tornado I would build with ICF walls and SIP roof panels strapped to the walls and metal roofing on top of that. I would also try to orient the house so it had as little exposure to the direction that storms normally come from as possible (straight line winds can do a heck of a lot of damage before the tornado ever hits you).-Day
restorationday,
All valid points which I vastly exceeded. You mention penetration, well my walls are 16-17 inches thick. Clad with solid hardwood timbers and stone..My garage door is a tuck under, sheltered on 3 sides by stone retaining walls. In addition the more vertical the roof is the less potential for lift there is. My roofs are 27/12 and 17/12 pitch that steep will cause air to "stall" rather than create lift.
I do expect windows to be shattered but you need a basic course in aerodynamics to understand why that isn't fatal if the rest of the structure is strong enough. To overly simply things it's like compressed air shooting out of an air hose. High pressure air expands once in the house the relatively large area of the room will not pressure up. Take an air hose and shoot it in a window of your car.. the volume of the car is too large to allow enough pressurization to cause the sort of damage that is required..
I do agree about the strength of ICF walls and in retrospect I would do that over my double timber frame (timbers inside and outside of the SIP's panels) That would also provide you with Impact resistance..
When you have a tree or your neighbor's car hit your house at 150 mph what kind of strapping, sheeting, or foam insulation you have doesn't matter a lick.
To quote Ron White: "It ain't that the wind is blowin'...it's WHAT the wind is blowin'."
Jason
If that Mosquito you keep bringing up was securely tied to the tarmac and it got caught in the vortex of an F4 or F5, would it be airworthy after the storm passed?
Notchman
Several reason it most likely wouldn't.
First is impact resistance although the mosquito was well known as a rugged absorb battle damage and still get back home aircraft.
Second the likelihood of a way to tie the aircraft to the tarmac without over straining local tie down points is problematic at best.
I do know the aircraft we took into typhoons in the Pacific required all aircraft to be tied down below decks.
By the way the vortex isn't were damage occurs it's at the peripheryWind in the vortex is calm..
It is going to take reinforced concrete to stand up to an F5. And/or being underground at the time.
Building a house that can stand up to 300MPH winds is one thing. Building a house that could take an impact from a telephone pole going 300mph is another thing.
You should probably be satisfied just to have a room in the basement that you can retreat to. IIRC, BossHog included a tornado shelter in a house he built a few years back.
jt8
"A little 'enthusiasm' and all problems seems small!"
"IRC, BossHog included a tornado shelter in a house he built a few years back. "
Yup - A concrete room under the 8' by 8' front porch.
The Big Bang Theory: God Spoke and BANG it happened.
Always nice to know you have somewhere you can go and be safe from the damn things! LOL, not that you're going to be using that shelter anymore, but you get the idea.
jt8
"If we don't put effort into creating what we want, we must then put effort into coping with what we have." --EPNIA
"Building a house that can stand up to 300MPH winds is one thing. Building a house that could take an impact from a telephone pole going 300mph is another thing. "
You are correct . While I dont know a lot about this subject we have at least a few tornados every year. Im 56 . Ive worked a bunch of damage and seen a lot more than my share . Poles go down and wires cross causing fires. The most incredible damage other than wind it self to a structure is big trees and particles in the air like shingles. Ive seen shingles many times driven 1/2 inch deep into wood. I seen the same thing in bricks .
Im just guessing a concrete dome is the best structure above ground but I dont know if it can withstand a 150 year old oak. We have a lot of large trees in our yards towering over our houses. I guess if we were picking we could pick a place like the plains of Oklahoma that doesnt have tress. I know theres lots of places like that but a tornado carrys boats ,trampolines , glass , shingles , etc with it .
We have lots of steep hills and mountains . Theres some underground homes built here facing the South that are open on that side. Theres also dirt on the roof with grass. Best I remember the dirt is a cushion for a tree falling and protects the roof material from the sun.
Tim
Mooney,
300 mph winds won't project a telephone pole at 300 mph. Due to it's weight and realitively small surface area it's highly unlikely it can travel at more than 150 MPH.
However direct impact with a telephone pole at virtually any speed will go right thru a typical stud wall. Or even a stud wall with Stone/Brick veneer..
It will not however go thru a ICF wall..
Ted,
It can be done. Think commercial construction. Steel and concrete. I'd go with ICF, like the video you posted. Use the widest ICF block you can afford for the thickest walls. Use plenty of rebar, and add a few pieces diagonally to take more shear loads. The roof should also be steel and concrete, and needs to be tied well into the wall structure. Make sure the foundation goes deep as well. Spend extra for high strength concrete (more cement and less water). Add a super plasticizer to the mix to allow it to flow better.
You can get special windows that can withstand repeated direct impacts. The glass will shatter but the membrane will keep the shards of glass from flying into the house. Better yet, use extra heavy roll-up steel shutters over the windows and garage doors.
A cement-based siding like stucco would be good. Surface damage would occur in a tornado, but it would be easily repairable.
Cost will be high, but it would be the only house standing after a tornado.
Paul Formisano, P.E.
Take a look at the 1990 Lockheed building (West of Plants 5 and 6) on the West side of Forth Worth - think that is made for an F5 except for the front lobby doors.
Cost will be high, but it would be the only house standing after a tornado.
Interesting. You pretty well described my house, which wasn't expensive to build. On a similar client house we discovered on appraisal that it came in 50% higher than construction cost, directly comparing it to stick built here. The appraiser ignored the energy savings. The shell wasn't the entire reason, but a significant part.
I got lost on junkhound's 300 psf. That's my total load roof design. Lot of dirt up there, next house will get more. When the top 50' of a tulip poplar came down on it one night, we were unaware. Found it the next morning, no damage. As I understand it, that's due to soil arching. Wind, we'd heard. Which is pretty unusual in here, takes a lot to get our attention. This was a hurricane remnant.
We don't have steel shutters, glass would indeed fly. Is the roof pressure up or down? If up, I'm assuming that our windows give out long before pressure lifts our 240 ton roof. Which is well-tied into the reinforced concrete walls. No wimpy ICFs, my primary walls are 12-14" thick. Side walls 8".
It never gets hot or cold in here, which was my reason to build this. As you mentioned, common commercial construction. Not expensive. PAHS works. Bury it.
VaTom
You are fortunate indeed to live where temps aren't excessive at times..
Here in tornado alley we suffer from +100degrees to minus 40+ degrees and insulation becomes critical.
As far as ICF's go you can use up to 15 inch forms for the walls which provide you with 11 inches of steel reinforced concrete. I wouldn't exactly call that wimpy!
"Wimpy" was a joke, as I presume you understood. However... Sorry, "11 inches of steel reinforced concrete" won't make my engineer happy. Or get my permit past the plan approver.
Regarding climate, you have 682 cooling degree-days to our 1131, and almost exactly twice our heating degree-days. Really not a big deal.
The original PAHS was built in a climate with your heating needs, but with considerably less (<50%) summer heat to charge the mass. Outperfoms my place. PAHS would work perfectly well in your climate, had you chosen to use it.
Luck had very little to do with our location decision. We did a lot of looking first, chose carefully. Still happy with our choice. Hope you are. I was just reading about inner-city development there. Very interesting, the choices some there are making. Encouraging. PAHS works. Bury it.
VaTom
Based on my actual numbers I suspect I've got less than 4 cooling degree days with the location of my home. I won't even unwrap my A/C units ( 2 small window units stuck in the wall) untill the middle of July at the earliest.. By Sept. they are wrapped back up..
Heating though is so dramatically reduced from previous use of heating with exactly the same furnace, twice as much area and three times the number of windows.. I am using less than 1/3 of my previous amount.. (in spite of cost increases)
The house is warm enough that I walk around barefoot all winter long. (and not completely sealed up yet) Plus I was home all winter. Previously I could set back the temps during the day.
As for site location I am shaded to the south by my up hill neighbor The house is oriented to the east and west where the views are.. Thus I get little solar gain in either the winter or summer.. The one portion of the home exposed to the southern sun has Ivy climbing all over it.. thus providing even more shading.
Ted
As Luka said it's hard to beat a Monolithic Dome. I live about 50 mile north of Italy Texas (Home of the dome) and have seen one of the domes that survived a tornado. No damage to the structure. Only hte outside covering showed it was hit by a telephone pole.
The domes can be built for about the same cost as a stick built.
Check out the following story:
http://static.monolithic.com/gallery/homes/morgan/index.html
Later
It was generally assumed that 'tornado proof' was pretty much a fantasy ... with the possible exception of nuclear reactors (where cost was no object) .... for ordinary construction. Then came the 1991 (?) tornado that hit Plainfield, Illinois.
That F5, if you look at the aerial photos, flattened the local high school, then crossed the street and, like a bride, went straight down the aisle of the local Catholic church. To everyone's amazement, the main part of the church survived quite well.
The secret? The farmers who had the place built chose (for the 60's) a pretty edgy design ... the main church was made by inflating a big rubber caterpillar, laying rebar over it, and spraying it with concrete. The windows looked like stained glass, but were really lexan, and designed to withstand 90mph prairie winds.
The part over the altar was of more conventional construction, and ceased to exist.
Tornadoes have two major means of causing damage. The first is the creation of a partial vacuum - hence all the accounts of them 'sucking' roofs off houses and picking up cars. The other is related to the high wind speeds; they toss debris very fast, and this debris causes the bulk of the damage.
renostienke,
I think if you look you won't find a home made with ICF's destroyed in a tornado. ICF's achieve what that expensive big rubber caterpillar did at a tiny fraction of the cost while providing insulational value..
You may be right. My comment was not to insist upon any particular construction method, but to counter the 'conventional wisdom' that, prior to the Plainfield tornado, held that no structure could be expected to withstand a direct strike. Prior to that, even the Nuke guys would waffle. So, there IS hope. Just remember the pressure issues ... the vacuum created by a tornado tends to pull structures apart, as the higher pressure air inside pushes the walls outward. That's why windows typically wind up outside the home. Again, Plainfield offers hope; the 'stained glass' amazed all by coming through unscathed ... they were not designed for that! It's kind of like running the 4-minute mile .... something considered 'impossible' until it was actually done .... then quickly performed by several others.
renosteike,
I really like ICF's as I said now that I've built with Both ICF's and SIP's. However prior to start of construction I had no idea of the values of ICF's over SIP's thus I built with SIP's above the foundation..
When I built my place because tornados were possible I built a double timberframe.. massively strong walls. And a massively over engineered roof attachment.
Just before I started construction straight line winds hit my nieghborhood doing some damage to my house and taking two massive trees. (took the roof of my neighbors house).
My calculations are that this place will easily withstand a level 5 Tornado, (The worst on record in Minnesota was a level 2) I think I could have saved a great deal of money had I built with ICF's instead of SIP's
Ted,
Here is a before and three after pictures of the tornado damage.
That should give you a better idea of how the structure failed.
Bryan
"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
What I don't see is any sign of the doors, the side wall or the back wall. Looks like the tornado sucked them right out and the roof came down.
Sure looks like a nice day there now, besides the garage being collapsed. You sure got your work cutout for ya. --------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
Ted,
The back and side walls were in the yard behind the garage. One small section of the back wall is yet to be found. The one garage door was up against the back of one of their vehicles. One section of the other garage door was behind the garage. The other three sections were found, still together, about a mile away. One of the entry doors have yet to be found as well.
As I think I mentioned in an earlier post, the homeowner thinks that the roof lifted off the wall, and the tornado then sucked the walls out, allowing the roof to collapse onto the vehicles. Again, there were no Simpson rafter ties as had been specified in the original plans.
Here's a picture of the area now.
Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
Would rafter ties have made a difference? Not trying to be a smartarse here, genuinely curious.
Jason
Jason,
I think it has been mentioned here already, but if you can keep the roof on, you will have a better chance of not losing the structure. If rafter ties would have been used, the garage might have fared better.
As it was, there was very little resistance to uplift with only three nails per truss into the double plate. Added to that was the lack of adequate attachment to the foundation. If you look at the pictures, it was also not well attached to the second story where the trusses were nailed to it.
And, being a garage, once the overhead doors are compromised, then there will be a greater chance of losing the whole thing.
Would the doors have been totally ripped out if the roof would not have been lifted off the wall? Hard to say.
One thing I do know, the garage we had built three years ago suffered minor damage. The large overhead door has to be replaced due to flying debris hitting it. There is vinyl siding on it all the way around that will need to be replaced due to being cracked from debris. Yet, the structure did not move. A fairly large pine tree closer to that garage was twisted off about 10 feet off the ground, and it was only about 30 feet from it.
So, would rafter ties have helped? I personally think they would have. Will I have the opportunity to find out in the future? I certainly hope not!
Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
I continue to be amazed by the precision of a tornado strike. Garage gone, house pretty much untouched. Incredible!
The original house is basically post and beam construction. The cupolo on top of the house had all the windows blown out of it. If it were a cupolo built today, it would have been gone.
The corner posts of the cupolo are at least 6 x 6's, and they go from the roof to the basement. We are pretty sure the cupolo, as well as the rest of the house, was twisted by the tornado. There are hairline cracks in most of the rooms of the house. Not a lot, but enough that we will need to repair them and repaint every room.
I will try to post a picture of the cupolo later. I don't have a good picture of it right now.
Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
Here is a picture of the cupolo. It's approx. 8 - 10 feet tall.
Does anyone have any suggestions on how to vent this other than the vent that is there?
We are going to be adding ridge vent to the four peaks of the roof around it.
Thanks, Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
You may want to start another thread to get more answers, but I have some answers and more questions:
How big is the cupola? Maybe doesn't even need venting.
If it does need venting, maybe just screened gable vents--the decorative round, oval or rectangular ones (or even arched vents) with slats may be fine.
Other option would be a "hot roof" on just that roof where you foam the underside and no vents.
Danno,
The entire second story roof is vented through the cupola. We are adding ridge vent, but that in itself will not be adequate.
Right after the tornado, the attic area was not hot. But then, there was no glass in the the cupola windows, so hot air was able to escape and be exchanged very easily.
That is why I am trying to install gable vents in the second story gables. There are decorative round trim that I think I can install a round gable vent in. This will allow more air to enter the attic and be able to exhaust through the ridge vents and the vent in the cupola.
I was just looking for suggestions on how a vent could be installed in the cupola different from the way it currently is, so that a full window could be installed there.
We will probably just leave the vent as is in the cupola.
Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
Don't know if this would apply to your situation, but if you just replaced the windows with vents? I saw in This Old House magazine where they built a sort of hopper so that any water blowing in the vent through the slats was directed back out--draining out the bottom.
Thanks for the suggestion, Danno.
I think the homeowner wants to keep the vent the way it is, with windows in the rest of it.
Bryan"Objects in mirror appear closer than they are."
Klakamp Construction, Findlay, Ohio - just south of the Glass City
Well ... they are "solider and better" ... solider??? Great spokesman for the IFF company.
Yeah foam form houses ... great for hurricanes and tornady's. Better yet, go earth shelterd and let the wind blow right over you.
Foam forms aren't really new .... there are a LOT of mfg. out there w/ lots of different systems designs. They do cost more ... concrete is heavier than wood ... therefore more expensive ... plus the finish work can be very different (more expensive??).
If I lived in tornado alley (i.e. Kansas), I'd seriously consider earth shelter construction ... then my siding wouldn't blow off.
I think the term your looking for is 'more solidy'. <g>
I imagine living in an underground home wouldn't bee so bad if it was very well lit (light? lighted?) and didn't feel so subteranian. I'm currently in a basement apartment and can't wait to move up to a real home. But an underground shelter doesn't have to be a closed box.
I'd probably have a waterfall in the middle of the living room, and lots of plants and those blueish (bluey? blue like?) light bulbs. Will have to keep a secret stash in case congress makes us go florescent.--------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
FYI ... he did say "solider"
Well lit ... absolutely ... earth sheltered does not mean dark and dingy basement living. Quite the opposite. Properly designed, they often have as much daylight as any house and more than many poorly designed stick framed houses with holes punched in for windows.
Clewless1
I'm sorry, finish work on ICF's is easier not harder!
There are tie points where the sheet rock is attached every six inches not every sixteen. Wiring, plumbing, etc. should be done prior to pouring concrete. So it's easier to do that as well. Much easier to cut thru foam than to cut thru wood! Windows and doors are installed the same way as usual, nailed to the wood bucks which form the openings..
Plus it's a lot easier to lift a 2 pound foam block into place than hoist a piece of plywood so construction is a whole lot easier..
Since most concrete comes locally and most wood is shipped long distances those costs too are similar..
Only 2% of new homes are constructed with alternative methods. That includes SIP's, Hay bale, and etc..
So 98% of all builders have never built with ICF's (actaully probably 99.5% since I see so many ICF homes built by a small handful of crews) once it becomes more accepted costs will plummet and speed will increase.. The first stick built home you did took a lot longer than they take you now.. That's the learning curve..
If I was a builder I'd jump right into ICF work and never look back.--------------------------------------------------------
Cheap Tools at MyToolbox.netSee some of my work at TedsCarpentry.com
Your points are well taken. New technology/techniques are often branded 'more difficult' because of the venture into the unknown. Often it is no harder ... just different skills required, a little different mindset.
Don't know if I agree w/ the concrete being same cost. I admittedly haven't run numbers. While concrete may be 'local', cement often is not necessarily 'local' as may be sand and aggregate. Concrete construction in general can tend to be more expensive. Plus the forms tend to be expensive ... although you save a bundle on labor!
Also, if your walls can withstand a tornado ... you still have a roof. Once it blows off and all of your contents blow out ... not sure if there is an advantage. Your roof may become your weak link ... unless you use concrete there, too!
Clewless.
The trick as near as I can tell is to keep the roof on. Nails won't cut it,, Simpson straps work well, Lag bolts work better..
The trouble is everybody is used to micro examining every facit of construction. There is absolutely nothing made in this world that cannot be made cheaper if standards are made looser.
2x4 walls are over kill in moble homes.. yet I see few houses built that way. even though there clearly is a cost advantage.. You can build with 2x4 walls or 2x6's and few people will blink at the differance.. There are also people who want the sound absorbing advantages, safety, and thermal protection of ICF's and are willing to pay for it.. the only difficulty is making those items well enough known that people are willing to step up and seek them..
Once widely accepted the total cost of ICF's will tumble Much like levit cut costs in his first homes..
That's not as hard as it would seem.. I mean people ask for Jucuzzi Tubs yet I see few people use them for anything other than a bath tub after a relatively short time..
It's the same with many must have features.. It's been made Cool/neat/ or a must have.. and the herd just follows..
Seriously, did the guy in the video say "Solider"? As in more solid, or most solid?