The Engineering That Survives Hurricanes

Florida is a great place to live, especially around January when it’s sunny and 24 degrees outside (76F) while all of your friends from back home are dealing with scraping ice off of their windshields every morning. In the late summer, though, this pleasant tropical paradise can sometimes take a turn for the worse, because Florida is one of the handful of places that frequently see some of the worst storms on the planet: hurricanes. As a Floridian myself, perhaps I can shed some light on some of the ways that the various local governments and their residents have taken to mitigate the destruction that usually accompanies these intense tropical storms when it seems that, to outsiders, it might be considered unwise to live in such a place.

The Storms

Hurricanes Matthew (2016) and Irma (2017) came very close but the centers of the storms were far enough away to limit damage in my area.

Before getting into Florida’s extremely robust building codes and unique building materials and styles, lets take a look at a hurricane itself. A hurricane is categorized on the Saffir-Simpson scale based on its maximum wind speed, which is a loose correlation to how much damage the hurricane will cause if it makes landfall. For tropical storms one can expect to lose a few palm fronds and dead branches from trees, but a category 5 storm can level entire communities.

While more intense storms can be incredibly dangerous, its important to realize that the strongest winds surround the eye at the center, and the wind speed falls off exponentially as the distance from the eye is increased. This means that a grazing blow by a hurricane will not see anywhere near the destruction that will be caused around the eye’s path. Further, the northeast corner of the eye wall tends to be the most devastating part of the storm, which is what saved Florida (and myself in particular) last year when Hurricane Matthew grazed the east coast of the state, keeping the more powerful part of the hurricane largely offshore.

Hurricane Andrew (left), a Category 5 storm which in 1992 was the costliest hurricane to make landfall until Katrina in 2005. Hurricane Floyd (right) made landfall in North Carolina as a Category 2 despite its much greater size, although at this point it was Category 4. Photo courtesy of

It’s also important to note that the force that the wind imparts on any object goes up with the square of the wind speed, which means that the difference between a category 1 hurricane and a category 3 hurricane can be striking, even though the wind speed only increases by 16 mph. (This is the same effect by which drag on vehicles increases exponentially with increased speed.)

Engineering Our Way Out of It

One of the more obvious solutions to living in a place like this is to simply use more robust materials when building homes and other infrastructure, and indeed that is the case for some modern homes. A common construction method, although slightly more expensive, is to build homes out of concrete block and then to fill the voids in the block with poured concrete. From there the roof can be made of concrete in some situations or can be made of heavy wood with reinforcing metal braces. Using metal as a roof surface material, rather than shingles, also helps improve the home’s tolerance to wind. Additionally, bridges, buildings, and other infrastructure are built more robustly as well to withstand the high winds of a hurricane. The skyscrapers in Miami, for example, are built to withstand wind speeds of 140 mph to 180 mph (depending on when they were built), which is certainly a higher design consideration than the skyscrapers of any other city like Phoenix or Detroit, for example.

A concrete roof is lowered onto a hurricane-resistance concrete house. Photo via B&A Architecture.

For homes that are made out of wood, however, special attention is made to how the roof is attached to the walls, and how the walls are attached to the foundation. One quirk of how high winds affect homes is that they tend to lift the roof upwards and off of the structure. To prevent this uplift, metal hurricane straps are nailed to all of the roof rafters and the roof is nailed with more hurricane straps to the wall. The wall is, in turn, bolted to the concrete foundation with special concrete anchors. These straps and anchors allow wind loads to be evenly distributed to the ground, and for the roof to resist any upward force.

Minimum wind speed (mph) design criteria for buildings and structures in Florida.

It might seem counter intuitive that the hurricane would lift the roof upwards, but as a result of the wind’s flow over a structure uplift is generated in much the same way as an airplane wing. This is why, in addition to making sure the structure itself is as sturdy as possible, the weak points of the structure must be reinforced as well. Often with hurricanes the damage isn’t so much from the wind, but from what the wind blows. And, if a 150 mph wind picks up a 2×4 or tree branch or fence post and launches it into a normal window, that opening will allow wind to enter the home and generate even more uplift to rip the roof off of the structure.

An opening of 1% of the size of the windward side of a building is enough to remove a roof. For that reason, specialized hurricane shutters are fitted to windows and doors or the windows themselves are built out of special impact-resistant glass that will shatter but remain intact, thus helping to protect the rest of the structure. Additionally, no modern building code in Florida allows for homes to have doors that open inward so that the entire jamb can take the brunt of the wind, and not just the latching mechanisms.

There is one other impact that hurricanes can have on the areas they reach, and that is torrential rain and flooding. While there’s no feasible way to build a flood-proof building, a choice of building site based on flood plain maps that the federal government maintains is often prudent. Also, living on barrier islands that are prone to storm surge is not advised either although building on stilts can help lessen the damage from a surge. On the other hand, some storms like Hurricane Harvey are so unprecedented that there is often nothing that could have been done that would have improved the situation at all.

Even with the improved building codes in Florida, no amount of concrete or hurricane straps would have prevented all of the damage that Hurricane Andrew caused, and no amount of drainage systems would have prevented all of the damage that Hurricane Harvey caused. Certainly there are risks to living in a place like Florida, but there are some pretty big rewards as well. While the winters are more tolerable than most of the rest of the United States, the surf can be pretty gnarly, and until I can afford a home in California or Hawaii this will have to do.

84 thoughts on “The Engineering That Survives Hurricanes

    1. It would be more accurate to say that while it could have been possible to design buildings to not have any problem with it, the storm was weird enough and the precautions required were extreme enough (depending on exactly where you were located) that a reasonable person would have looked at the costs and said, “Nah, I’ll take my chances… seriously, what are the odds we’ll have a Category Four hurricane park itself over the city for a whole day?”

      1. The author seems to be more concerned about the flooding and unsuitable drainage systems here though?

        Also, it’s worth nothing that Harvey was technically a category 4 when it made landfall but quickly dropped to a category 2 within about five hours.

        The chances that you will continue to have hurricanes over areas that regularly and habitually have hurricanes are pretty good. It seems like nobody ever wants to pay for things until afterwards though but it’s also that scaling up things like drainage systems does not scale the costs linearly either.

        1. If you move to a place that’s had some hurricanes or tornadoes, buy a portable generator. Also buy three two gallon gas cans and some Sta-Bil. Fill all three cans. Each month, use one in your car then refill and add Sta-Bil. Rotate the cans so you’ll always have gas that’s one, two, or three months old but no older.

          At the start of storm season, make sure the generator runs then fill the tank and add some Sta-Bil, then run again for a bit to get it through the fuel system.

          You’ll have a generator and a good fuel supply for it just in case – unlike all the nuts that wait until a storm is bearing down on their town to try and buy a generator.

          1. Get a propane generator, propane has a longer shelf life and you can rotate the tanks with the BBQ, they also tend to be quieter, so fewer neighbors complaining about the noise or asking to charge up their devices.

          2. The absolute best hurricane and power outage survival advice I’ve ever heard has come from Steven Harris. He gives all kinds of unorthodox and inexpensive ways to power through blackouts. Google his name and listen to some of his recordings. Opinionated, but his opinions always have strong reasons.

          3. He (Steven) for example talks about things such as powering your whole house from your car. Not everything mind you, but enough basics to make getting through possible. (I wish HaD comments were editable like the rest of the world now.)

          4. Be careful with Sta-Bil and products like it. I fix small engines on the side and 20% of the ones I’ve worked on stopped working due to the carburetor clogging up with a gelatinous goo from fuel stabilizers. People think more is better and add too much.

            Propane generators aren’t necessarily the answer. Propane has a long shelf life, but there is a lot less energy vs gasoline. 3 BBQ sized propane tanks don’t last nearly as long as 3 5 gallon gas cans. It’s also a lot harder to find someone who knows how to fix a propane generator which can be a major issue if it stops working during an outage.

          5. I use a generator in the garden house some times (and a lawn mower), of course some gas sits there during the winter season. There is no problem with it although I have never heard about “StaBil”. So it seems to be OK to rotate the cans every 2-3 month and not spending money on (probably expensive) additives.

  1. I always thought a pyramid design would work for wind, nothing for the wind to grab to rip the roof off, angle of the walls would deflect force at a tangent instead of straight on. Flooding would be an issue but, what can you do, raise the whole structure on very strong, very expensive cylinders after the storm passes but until the waters recede?
    Build it on float able material with cables anchored so it doesn’t float away and will lower as the water goes down?

    I’m not s mechanical or a structural engineer but, from what I’ve seen,neither are the people building houses in the USA. I visit islands in the Caribbean (3rd world countries) and I gotta say, some of the nicer homes are built nice. I’ve seen some things inside and out and thought “I’ve never seen that in any house, new or old, in the United States!, why don’t they do that back home?”

    or, maybe one of those houses that have round, golf ball looking spaces. Again, not sure on that one.

    1. A design consideration, would be to build a “car port” at ground level, and the house above it. This can have the same effect as stilts, but making the space useful. I saw a video of such a house on a Texas barrier island that was the only one standing in its neighborhood, after a hurricane a few years ago.

        1. It’s common in Florida as well. Unfortunately, that’s not a cure-all. I saw some pictures of post-Irma properties in Northeast Florida where the storm surge partially or completely washed out the sand under the house. One house was left falling over the edge of a 10-ft sand cliff. Another had the concrete floor of the under-house garage dangling in mid-air.

          Inland flooding was incredible and it’s not over yet. All that rain that got dumped in the swamps of Central Florida is now making its way downstream, flooding downtown Sanford, north of Orlando as well as other places along the rivers. And Irma was 2 weeks ago.

    2. How about this… The floor is built on a large float that is recessed into a pit so the house still sits at normal ground level. At points around the edges of the float are beams sunk into loose fitting shafts going deep into the ground that are fitted with ratchets and a tapering mechanism at the top so that as the area floods, the house begins to float being held in position by the shafts. As the water level subsides the ratchets hold the house up so that the pit recess can be cleaned of any debris then the house lowered back down once it’s clear and safe to do so. Services could either be connected by flexible conduit or break-away self-sealing connections..

    3. “I’m not s mechanical or a structural engineer but, from what I’ve seen,neither are the people building houses in the USA. ”

      True, but that’s because Engineers don’t typically build things. Engineers design them. The people designing and approving the house structures and building codes are civil and structural engineers. Also, mechanical engineers don’t typically do buildings, that’s for civil engineers.

        1. A storm like Katrina throws around more power in a week than the whole human race uses in about 15 years. The amount of energy from the Sun hitting Earth each second is enough to power many Katrina sized storms.

          Anything humans can possibly do is spitting in the ocean in comparison.

          These Atlantic storms? They’re puny compared to what the Pacific can whip up. Look up Typhoon Tip. That one was in 1979. At its largest it was nearly 3,000 miles diameter. Fortunately it shrank a lot before making landfall in Asia.

          There is no ‘trend’ in any direction of the size and power or number of tropical storms. A look at the numbers going back to the earliest records shows they’re completely chaotic. Some times there are many storms, some times very few. Some years no storms make landfall. Some years most of the ones that happen make landfall. 2005 was a record year for Atlantic tropical storms reaching the minimum thresholds to get names, but from then through 2017 there have been few storms each year. Three storms at once in the Atlantic is NOT unprecedented. It’s happened before.

          Something we can be sure of is that before satellites and storm hunting aircraft, there had to be some tropical cyclones that stirred up and dissipated without anyone ever knowing they happened. Before there were specialized aircraft to search for anf fly into the storms, before weather satellites, the only way to know a tropical cyclone existed and where it was before hitting a continent was if it hit an inhabited island or happened to cross a shipping lane and there was one or more ships in the way.

          It would be interesting to take the observations from the start of the satellite era to now and remove any tropical storm that would’ve passed un-noticed without a satellite to spot it. If it hit no land and crossed no shipping lane, set it aside from the list of storms that directly affected people.

          Then you’ll have something to work with for guesstimating how many storms *might* have been missed prior to weather satellites.


            What is unprecedented is the ocean temperatures that FEED the storms, that’s the overwhelming issue. A lot of these storms would’ve normally lost steam a lot faster than they did, but the Gulf is warming at a never before seen rate.

        1. Precisely. You need something ocean-sized to store that amount of energy.
          I was just pointing out a technical hurdle of the OP’s suggestion, “Imagine harnassing the energy of a hurricane!”. It’s not only harnessing, it’s storing.

        2. Historically we exploit resources wastefully, to the detriment of the ecology, and to the point of exhaustion. Artists creating Dr. Who called it right, other species near us tend to suffer. Hydroelectric dams blocking salmon migration, wind turbines surrounded by dead bats, bald eagles in the 60’s wandering drunk on the road from DDT, fish consumption signs posted by the state warning should not eat more than x fish from these waters per month, there’s a long list.. Am no ecology nut, just observant, easy to see the effects for yourself.

          What harm could be done using the oceans as a heat source or sink? Bouillabaisse? Sardine Icebergs? Any water turbines would have to be enormous… whale, dolphin, and shark blenders? Quit giving these guys ideas!

    1. In Florida we have storm panels. These can either be an expanding (accordion) design that hides under the faux shutters or if you are poor like me they are steel sheets that get bolted over the windows. They are mainly there to keep garbage from getting blown thru your window and into your living room like normal shutters. We do have 220 mph break resistant glass which helps, but the wind and flooding are major probs with a storm like this. Flooding is addressed by the drainage canals and is greatly affected by which side of the intracoastal waterway you live on. We got lucky and only had some wind damage to trees. The real biatch was losing power for 6 days and having to share a cell tower with other morons that think it is open season to upload all of their gigabytes of files of wind and rain videos to the cloud later. Then AT&T also forgot they gave us a data requiem for disaster travel which was great so we are now a few hundred megabytes over. All in all we were lucky though.

      Overall the scariest parts for me for this hurricane was the absolute shit job many of the weather outlets did at providing MEANINGFUL information in an easy to find format. That was absolute garbage. Infuriated me to no friggin end. I ended up just sticking with NOAA. But shame on the actual weather sites and whatever clickbait-oriented SEO was in play for both google and bing. I guess some of the warning stuff was shunted by the islands that got hit at the time, but they also gave (at least me) very little info to go on there. No windspeed, actual surge levels or anything useful. It was shit.

      The other ball-buster was the evacuation. It was end of times level shit. A 3 hour trip north took us 10 hours. Yes, 10 hours. We left at 3 am and got there at almost 1pm. The sides of the road were littered with broke down cars, out of gas cars, and people peeing in the bushes and walking their dogs. A couple of the service islands on the turnpike were out of gas, which sucks ass on the turnpike as you don’t have many options for seeking out other. We ended up not daring to stop and pee and sat in the truck without AC so we had gas to make it and not end up like those poor other souls on the sides of the road. Apparently, to add to the idiocy, the highway patrol in Georgia had okayed for people to drive on the shoulder, which apparently some folks thought meant Florida too. Florida drivers are some of the biggest assholes and jackasses on the planet. They did not disappoint. I was thankful of the one guy in the F350 that shut one group of 200 off. They were honking and mad but f$#% them, I sat for an hour and a half for what they were trying to drive in 15 mins. Thank you again, F350 dude!

      We lucked out the place we stayed had been planned. The neighborhood had buried power lines and all else. We had power and internet througout the storm. Only after we returned home did we sit in our sweat for 6 days. There again, the good folks at FPL worked hard to get things fixed and going but their outage map never worked and they literally hooked up 75% of our neighborhood before moving on. If I hadn’t been spamming support tickets, I doubt we would have gotten it back until Sunday. I really hope they look into improving the electrical infrastructure, though by my understanding they already have. This place is just a sandbar waiting for a high enough tide lol.

      With all that said, I do feel like we got off very lucky this round. I feel really bad for the folks that actually got hurt and lost their entire lives in the span of a few hours and I REALLY feel bad for Puerto Ricans stuck without fans. The storm took all the wind and rain with it so it is just stagnant air behind it. Hope they get some relief.

        1. It would be nice. I would guess that it is harder to service but then again you have to service it less. If only Tesla had gotten Wardenclyffe going full scale things would be much more manageable- just stab a rod in the ground and you are back off to the races :)

      1. Teatmouse. So you didn’t find that watching those same 3~5 people standing at the corner of a large building (holding a microphone & their hat) for three days, helpful?
        Well then surely all of the idiots waving a cellphone , back & forth like a paint spray gun, while taking skinny/sideways cellphone videos must have been worth the clogged cell service….NOT.
        I’m in one of what was a potential storm path and was a bit frustrated by some of the issues that you mentioned.
        I can only guess at the level of exasperation with national “media” for deciding on actual life & limb decisions that you folks were faced with.

        1. I think my fave of those news clips was the jackwagon that was trying to show surge/flooding in the street. He was slogging around in ankle deep water talking about the massive destruction to the island and then the camera pans left and he is literally in the yard of a beachfront home lmao. It was a shitshow for sure, Adobe. I really wish the media could go back to the days of less adjective-induced hyperbole. Just glad New York didn’t get hit or we would be hearing about it for the next three years lol. Glad ya made it thru safe, chief :)

          1. My favorite was the guys who went out to get selfies in front of the crashing waves, and ended up going ass over teakettle when a big one came in. This was on that stream with the white shed. Anyone know if Shed made it through?

  2. the main problem/concern is the wood based constructions, i know the building code is asking for it, but still, for me it is absolutely strange idea to live in a wood-house, here even the weekend houses are built from rock :) as for the main houses they are hundred years old and still solid as hell, i think the american wood-code is for most likely to not allow people to build something that can last for a long time, with wood they can dozer your home easy :)

      1. My house was built in ~1868-1871. The wood structure of the house is probably what’s in the best shape. All the masonry, metalwork, etc. hasn’t fared nearly as well.

        Then again it is made from a very rot resistant wood (red cedar) and mildly over built– the main beam is basically a rough cut tree and measures 5 1/2″ x 7 3/4″. :)

    1. Wood is cheap. Houses are expensive and people don’t want to pay “too much” for a house. That’s basically the driving force. At least on a large scale and commodity homes in the United States.

    2. I’m not aware of any widespread legal or code restrictions on using stronger materials — just stronger materials (and less-common construction methods) will cost more and most people aren’t willing to pay the cost. In my area, probably over 95% of homes have asphalt shingle roofs, with an expected lifespan of 15-30 years. Some have clay or concrete tiles, or slate, or metal, all of which will last significantly longer (and probably cost less over their lifetime, and have lower environmental impact) — but they cost more up-front, which is the number people look at.

      1. To use stronger materials well, you need an architect and construction outfit who know what to do. Or new codes. For example, if you stiffen up a code built house in California, you get worse earthquake damage.

  3. California has its own problems – seismic ones.

    Earthquakes are less frequent, but unlike hurricanes (nowadays), we get no warning at all.

    Ironically, the structural mitigations are similar: tie everything firmly to its neighbor and to the foundation. We just don’t need hurricane glass or shutters.

  4. Please go and look up stone houses here in Croatia.(senj town is good example) Some seaside placese have 200kmh winds all year round (winds called Bura). Real bulletproof design is good old brick and atone house.

    1. I always wonder why they build houses in the Marina district in San Francisco. Every time there’s a quake, the ground (which is landfill) liquifies, the buildings fall down, gas lines break and the whole neighborhood burns down.

      They dust themselves off and rebuild exactly the same buildings in the same place. I will never understand it.

    2. Builders can only build what those paying them tell them to build.. speculative builders are going to build what people will purchase. A vicious circle that’s damn near impossible to stop.

  5. I am curious, wouldn’t it just be better to dig a hole in the ground and live in there instead?
    Flooding is still a problem though…. But if one were to build it a bit more like a large mound, have a decent pump, and build it semi water tight, then it should get through even the worst hurricane, but will probably be expensive. And I do think most people also might want a window or three, among other normal things….

    1. Thing about Florida, is that the soil, is basically the same as beach sand. The caution us every storm, about not drain our inground pools, if the ground gets saturated with storm water, an empty pool will float up out of the ground. There aren’t many basements either, for a similar reason. It’s hard to anchor anything that floats, in sand. Most of the storm damage comes from water, not the wind. Most of the damage and failed structures were poorly build, or maintained. People are cheap, and know that insurance or disaster relief money will be enough to more than cover the damage, least until the next big storm. Not sure why people don’t see that it’s more of being cheap, than the storm, since the eye is miles wide, but the everything in the path isn’t flattened, just a few structures, a few trees. We have news crews riding out the storms in all the major cities, likely to get hit, yet they keep showing the same clips, same tree that fell, same houses the lost the roof…

      Some people just like to gamble more than others, they go cheap on the building and repairs, believing they’ll be fine for years. Only takes one to do the serious damage, but they get a new house built, new things, so no big deal, right? I’d rather have a house that will last, and I don’t want to lose all my stuff, many thing that can’t be replaced. I’ve never evacuated, doubt I ever will, just seems like a bigger risk, besides most shelters don’t let you bring your big dog with you, just too cruel to put him in a cage some place.

    2. Almost no one builds basements in Florida. It’s too expensive due to the soil composition and water table. Where I grew up you hit water after 2-3 feet of digging and solid rock around five feet.

      1. Solid rock at 5 feet is not good for a basement, at least expensive to build. You probably need some dynamite and heavy mining machinery. But it seems very good to securely anchor a house that shall not fly away in the storm.

  6. First rule of optimization: don’t.

    Which in this case means not exposing the building to the hurricane in the first place. Build underground or at another place. Solved.
    (Not entirely serious)

  7. Living in Sweden, far away from hurricanes and earthquakes I was still devistated watching the news of what happend in the US.

    Dont know if there is any protection against these kind of forces.

  8. For rest of the world: The skyscrapers in Miami, for example, are built to withstand wind speeds of 225 km/h to 290 km/h (depending on when they were built).

    Sorry, but i cant imagine anything in miles.

  9. The article correctly says, “the force that the wind imparts on any object goes up with the square of the wind speed”, but then goes on to contradict itself by saying, “This is the same effect by which drag on vehicles increases exponentially with increased speed.”

    Please. x^2 is not equal to e^x. A polynomial is not an exponential.

    There are mathematically illiterate journalists who hear scientists, mathematicians, and engineers use the term “exponential”, and the only thing they understand about the term is “really big”. They then misappropriate the term to mean anything that is “pretty big”.

    I fear that one day they may convince their mathematically illiterate lexicographers to write a dictionary definition of “exponential” that defines it to be “really big” but not “involving a variable in an exponent”. Please, let’s use the term correctly.

  10. I stopped reading after this pile of nonsense: “This is the same effect by which drag on vehicles increases exponentially with increased speed.”


    1. The laws and taxes and population density and traffic are much nicer in Florida, AND you can afford to live near the ocean, which is much warmer :-) And I’d rather know about natural disasters a week in advance (hurricane) vs. almost no warning (earthquakes). Thanks, I’ll stay in Florida ;-)

  11. “Florida is a great place to live”

    I guess all the people in the US joking about how you should avoid Florida are wrong then.
    Now I wonder if Detroit is a great place to live too.

  12. I too am frustrated by the misuse of “exponentially”. Incorrect usage of precise scientific language causes me to immediately distrust the entire article.

    “(This is the same effect by which drag on vehicles increases exponentially with increased speed.)”
    In this specific context, you actually mean that drag increases “quadratically” with speed. Also appropriate (but less precise) would be:
    “faster than”
    “at a faster rate than”

  13. I know painfully little about aerodynamics much less subsonic flows but if I was in the business of designing experimental houses and building in an area prone to hurricanes I might consider a cylindrical structure with a near-flat roof holding an upside-down “flying saucer”-shaped spoiler which compensates the high pressure flows on the flat roof by pressing downward. Instead of pinning the roof down the combined forces like Bernoulli’s principle and the Coanda effect of the airfoil would only be great enough to simply not let the roof be pulled right off the building. The top of the saucer and the roof itself need to be sloped to keep the rain off but could also be compensated by the greater convexity of the underside of the saucer.

    This would obviously be more expensive that the roof that goes on an A-frame house but would it work? I’d guess that in high enough winds the sauce would simply crush the house, flip over over and blow away like a house-sides frisbee of death. Hmmm.

    1. I was most impressed by a video I saw where some researchers had built some probes for reporting from inside tornados. They were conical (? round pyrimid) about 2′ in diameter and were placed in the grass in the path of the tornado. Not anchored. Not heavy. But they never moved despite a direct hit! Aerodynamics are the key.


    Umm…. almost all exterior doors I’ve ever seen in 62yrs of living in Florida open inward. Years ago, had to argue with the guys that walled in a sliding glass door and replaced it with a steel-clad door. I made them hang it to open outward both for better hurricane resistance and because it was primarily an escape door from the master bedroom.

  15. The article focuses on residential construction, but for factories, warehouses, and so forth you can’t do better than design to FM Global standards and FM Approved roof assemblies. They do “engineering that survives hurricanes.”

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