# What will happen to all the skyscrapers 100 years from now? **URL:** \ **Category:** Factual Questions\ **Created:** [June 7, 2012, 7:09am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357 "2012-06-07T07:09:43Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![KellyCriterion](https://avatars.discourse-cdn.com/v4/letter/k/b3f665/32.png) [@KellyCriterion](https://boards.straightdope.com/u/KellyCriterion)\ **Post date:** [June 7, 2012, 7:09am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/1 "2012-06-07T07:09:43Z")
I’m no structural engineer, but it occurred to me recently that with the relatively modern advent of building soaring skyscrapers, especially in such close proximity to each other, that these things surely can’t stand on their own forever. As time goes by, they surely structurally weaken, right? Foundations become brittle, etc? So how do you safely “bring down” a skyscraper that’s packed between numerous other skyscrapers when said skyscraper is deemed to be no longer structurally sound? Or is it possible, over time, to incrementally “replace” weakening support structures with newer, stronger support materials such that these buildings could potentially stand indefinitely? ---
**Author:** ![The\_Niply\_Elder](https://avatars.discourse-cdn.com/v4/letter/t/8e8cbc/32.png) [@The\_Niply\_Elder](https://boards.straightdope.com/u/The_Niply_Elder)\ **Post date:** [June 7, 2012, 7:26am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/2 "2012-06-07T07:26:02Z")
Foundations, such as bedrock, concrete, granite, et al are already by nature, brittle. They dont increase in brittleness as time goes on. Their brittleness is balanced by the ductility of steels and irons. There are roman-era concrete structures still standing, so there is no need to bring down a skyscrapper, unless the square footage on which it was built is so valuable it makes economic sense to build a bigger and better skyscrapper in its place. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 7, 2012, 7:57am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/3 "2012-06-07T07:57:35Z")
I believe these things typically have a specific service life in their design, but often, that just means they require some sort of upgraded maintenance after that period - it doesn’t mean they’ll start falling apart. I guess if you have to demolish a skyscraper in a confined space, you do it as (kinda) the reverse process of construction - strip out all the internal fittings, remove the skin, then start destroying it layer by layer, from the top. Half a skyscraper can support itself whilst being gradually constructed, so as long as it’s done with proper care (i.e. don’t saw through the branch you’re sitting on), half a skyscraper ought to be able to support itself whilst being gradually _de_constructed. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [June 7, 2012, 8:59am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/4 "2012-06-07T08:59:51Z")
As it happens, there is quite a bit of experience in the field of unbuilding skyscrapers. A recent (notorious) case is the old [Deutsche Bank Building](http://en.wikipedia.org/wiki/Deutsche_Bank_Building). There’s also an interesting book called _Unbuilding_ by David Macaulay which goes into how one might dismantle the Empire State Building. ---
**Author:** ![Nunzio\_Tavulari](https://avatars.discourse-cdn.com/v4/letter/n/b9bd4f/32.png) [@Nunzio\_Tavulari](https://boards.straightdope.com/u/Nunzio_Tavulari)\ **Post date:** [June 7, 2012, 11:27am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/5 "2012-06-07T11:27:31Z")
> [@KellyCriterion](#): > > So how do you safely “bring down” a skyscraper that’s packed between numerous other skyscrapers when said skyscraper is deemed to be no longer structurally sound? Fly a plane into it. ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [June 7, 2012, 11:56am UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/6 "2012-06-07T11:56:38Z")
[Scroll to the 6 minute mark](http://www.youtube.com/watch?v=NRnX4quv5W4). ---
**Author:** ![Koxinga](https://avatars.discourse-cdn.com/v4/letter/k/4af34b/32.png) [@Koxinga](https://boards.straightdope.com/u/Koxinga)\ **Post date:** [June 7, 2012, 12:07pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/7 "2012-06-07T12:07:00Z")
> [@Nunzio\_Tavulari](#): > > Fly a plane into it. You’re on the list, now, surely you realize. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [June 7, 2012, 1:17pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/8 "2012-06-07T13:17:38Z")
> [@Nunzio\_Tavulari](#): > > Fly a plane into it. No more flights for you! ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [June 7, 2012, 1:30pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/9 "2012-06-07T13:30:09Z")
In my neck of the woods, they’ve disassembled piece-by-piece a couple of medium sized buildings. One was a round building about 35 stories. That one was interesting. They took away the “outer” part of each floor from the bottom, leaving the central concrete core. After a bit it started to look like a weird mushroom. Once the outer part was gone, they broke up the core from the top down. In each case, they put up a bigger building on the lot. Usually, such real estate is quite valuable. So taking down the old, “worn out” or too small building and replacing it will likely be the fate of most such buildings. The main exceptions will be in places like Detroit where the property values are falling and the demand for space is decreasing. The likelihood of buildings just being left to their fate increases in such situations. If the cost of tearing down a building is more than the value of the property afterwards, expect the owners to default on taxes and let the cities deal with it. Cities like Detroit would have a hard time coming up with the money to tear a derelict large building down, so it will be interesting to see what happens. ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [June 7, 2012, 1:47pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/10 "2012-06-07T13:47:08Z")
Well, the Woolworth Building - all 57 stories of it - is 99 years old, so let’s see if it falls down next year. ---
**Author:** ![Mr.Miskatonic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mr.miskatonic/32/310_2.png) [@Mr.Miskatonic](https://boards.straightdope.com/u/Mr.Miskatonic)\ **Post date:** [June 7, 2012, 2:54pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/11 "2012-06-07T14:54:30Z")
The deconstruction of One Meridian Plaza is a pretty good example of how such things are brought down - while not the tallest of skyscrapers its 38 stories were in very tight urban quarters. > **[One Meridian Plaza](https://en.wikipedia.org/wiki/One_Meridian_Plaza)** > > One Meridian Plaza, formerly known as the Fidelity Mutual Life Building, Three Girard Plaza and Three Mellon Bank Center, was a 38-story high-rise office building in Philadelphia, Pennsylvania, United States. The 492-foot (150-meter) tower was designed by Vincent Kling & Associates and completed in 1972. > On February 23, 1991, a twelve-alarm fire began on the 22nd floor and raged out of control for nineteen hours. Philadelphia firefighters fought the blaze but struggled due to a lack of power in ... ---
**Author:** ![boytyperanma](https://avatars.discourse-cdn.com/v4/letter/b/4491bb/32.png) [@boytyperanma](https://boards.straightdope.com/u/boytyperanma)\ **Post date:** [June 7, 2012, 4:28pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/12 "2012-06-07T16:28:08Z")
If they are maintained they will last indefinitely. Some maintenance may prove costly enough the owners might decide it’s worth tearing down and rebuilding, but nothing stops them from keeping them standing forever. Keep in mind the worlds largest reinforced dome has stood for over 2000 years. Skyscrapers are built to higher standards with reinforced concrete. ---
**Author:** ![tdn](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tdn](https://boards.straightdope.com/u/tdn)\ **Post date:** [June 7, 2012, 4:34pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/13 "2012-06-07T16:34:06Z")
> [@Mangetout](#): > > I guess if you have to demolish a skyscraper in a confined space, you do it as (kinda) the reverse process of construction - strip out all the internal fittings, remove the skin, then start destroying it layer by layer, from the top. Or you could just do [this](http://www.metacafe.com/watch/467188/abu_dhabi_skyscraper_demolition/). ---
**Author:** ![John\_Bredin](https://avatars.discourse-cdn.com/v4/letter/j/96bed5/32.png) [@John\_Bredin](https://boards.straightdope.com/u/John_Bredin)\ **Post date:** [June 7, 2012, 6:06pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/14 "2012-06-07T18:06:50Z")
> [@tdn](#): > > Or you could just do [this](http://www.metacafe.com/watch/467188/abu_dhabi_skyscraper_demolition/). Not if there’s two still-in-use buildings wall-to-wall with the to-be-demolished building, or the L goes right past one side of it. :smack: The building in your link had the entire block to itself. The OP specifically referenced > [@](#): > > a skyscraper that’s packed between numerous other skyscrapers I’m sure he/she’s quite aware of the hundreds of videos of building implosions floating around on the Web. :rolleyes: ---
**Author:** ![anson2995](https://avatars.discourse-cdn.com/v4/letter/a/c77e96/32.png) [@anson2995](https://boards.straightdope.com/u/anson2995)\ **Post date:** [June 7, 2012, 6:12pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/15 "2012-06-07T18:12:17Z")
> [@KellyCriterion](#): > > As time goes by, they surely structurally weaken, right? Foundations become brittle, etc? A well-maintained building won’t ever degrade to the point that it needs to be torn down. The Two Towers of Bologna are about 300 feet tall, and were built between 1109 and 1119. There are churches across Europe that are over 400 feet tall – Lincoln Cathedral in London dates to around 1300. There are [10 story apartment buildings in Yemen](http://rarelyknown.org/2010/11/28/oldest-skyscrapers-in-the-world/) made of mud brick that date to the same time period. That material erodes naturally from wind and rain, but they make repairs and keep them standing. ---
**Author:** ![Mr\_Downtown](https://avatars.discourse-cdn.com/v4/letter/m/8e8cbc/32.png) [@Mr\_Downtown](https://boards.straightdope.com/u/Mr_Downtown)\ **Post date:** [June 7, 2012, 7:25pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/16 "2012-06-07T19:25:23Z")
> [@KellyCriterion](#): > > So how do you safely “bring down” a skyscraper that’s packed between numerous other skyscrapers when said skyscraper is deemed to be no longer structurally sound? Tall buildings, especially those from 80-100 years ago, seldom have structural problems, except with the outer masonry skin. They were generally overdesigned by today’s standards. But demolition is done quite often in major cities. They put up a crane to lift equipment and dump skips to the top, and identify a rear corner where the debris can go, or create a shaft in the middle where it can be dumped. Then they use little Bobcats with jackhammers and front-end loaders to chip away the concrete and move it to the debris shaft. Once rebar or structural steel is exposed, welders (sometimes hanging in safety cages) cut it into manageable pieces and it’s taken away for recycling. It’s cool to watch, and you always hope the consulting engineers are right about what parts can be taken away while the workers are running around in their Bobcats on the now-incomplete floor slabs. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [June 7, 2012, 8:06pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/17 "2012-06-07T20:06:33Z")
rocket engines are constructed on the lower floors. girders at this level are exposed and the rivets are replaced with explosive bolts. the rocket engines are fired creating thrust then the explosive bolts are blown. ---
**Author:** ![Baron\_Greenback](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/baron_greenback/32/48_2.png) [@Baron\_Greenback](https://boards.straightdope.com/u/Baron_Greenback)\ **Post date:** [June 7, 2012, 8:23pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/18 "2012-06-07T20:23:35Z")
It’s possible to remove at least some tall buildings cleanly from the bottom up: [http://www.newscientist.com/blog/technology/2008/07/how-to-demolish-skyscraper-from-bottom.html](http://www.newscientist.com/blog/technology/2008/07/how-to-demolish-skyscraper-from-bottom.html) ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [June 7, 2012, 8:30pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/19 "2012-06-07T20:30:50Z")
> [@johnpost](#): > > rocket engines are constructed on the lower floors. girders at this level are exposed and the rivets are replaced with explosive bolts. the rocket engines are fired creating thrust then the explosive bolts are blown. This would be cool, though. They could pay for it all by selling tickets to watch the lift-off. ---
**Author:** ![Dahu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dahu/32/3416_2.png) [@Dahu](https://boards.straightdope.com/u/Dahu)\ **Post date:** [June 7, 2012, 9:13pm UTC](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357/20 "2012-06-07T21:13:50Z")
> [@anson2995](#): > > There are churches across Europe that are over 400 feet tall – Lincoln Cathedral in London dates to around 1300. Lincoln cathedral is not in London, it’s in Lincoln (funnily enough). [Next page](https://boards.straightdope.com/t/what-will-happen-to-all-the-skyscrapers-100-years-from-now/624357.md?page=2)