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Since the events of 9-11 it has been claimed several times that no other skyscraper in history has ever collapsed from fire damage. It's usually used as a part of the argument that fire alone cannot bring down a steel-frames building.

The 911 research website claims:

Excepting the three 9-11 collapses, no fire, however severe, has ever caused a steel-framed high-rise building to collapse.

ae911truth.org has a list of other building that did not collapse and uses it as evidence to claim that:

...the Twin Towers and WTC Building 7, the only steel framed skyscrapers in history, whose… complete collapses have been officially blamed on fire

and to further claim:

overwhelming scientific, forensic, and eyewitness evidence that proves the WTC skyscrapers were not destroyed by fire

So I ask:

Other than the World Trade Center buildings, has fire alone ever caused a steel skyscraper to collapse?

  • While this question was inappropriately structured for Skeptics.SE, the fundamental claim being hinted at - that Tower #7 was deliberately demolished in a conspiracy theory that was broader than the conspiracy of 19 or so terrorists - is certainly notable and has been getting heavily promoted recently. It is addressed here: skeptics.stackexchange.com/questions/1368/… – Oddthinking Sep 28 '13 at 22:58
  • The OP included a link to video of a skyscraper fire that I have removed as unnecessary, but include here anyway: youtube.com/watch?v=eKvgD9NyIi4 – Oddthinking Oct 1 '13 at 10:36
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    slightly off topic, but I chuckle every time someone claims that the "twin towers" (as opposed to #7) were destroyed "entirely by fire", as if the high-speed impact of a huge jet airplane and sudden loss of huge chunks of material were incidental :\ – KutuluMike Oct 1 '13 at 17:11
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    the very idea that the WTC towers were destroyed "solely by fire" is ridiculous. The structural integrity of the buildings was severely compromised by the impact of several hundred tons of aircraft at 500mph+ already, greatly helping the fires. – jwenting Oct 2 '13 at 4:07
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    Im pretty sure that the WTC Were mostly destroyed by gravity... Fire was merely the catalyst to the structure succumbing to the pull of gravity – Chad Oct 2 '13 at 20:41
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Other examples?

There's a list of buildings which have collapsed due to fire here: Historical Survey of Multi-Story Building Collapses Due to Fire. Scanning this document, to include only building which are made of steel (and not e.g. reinforced concrete), shows only two:

Alexis Nihon Plaza Montreal, Canada

  • Steel frame with composite steel beam and deck floors; fire resistive without sprinklers
  • 15 floors, Office
  • Oct. 26, 1986, after 5 hour fire, which then continued for 13 hours
  • Partial 11th floor collapse

One New York Plaza New York, NY, USA:

  • Steel framing with reinforced concrete core, fire resistive with no sprinklers.
  • 50 floors, Office
  • August 5, 1970
  • Connection bolts sheared during fire, causing several steel filler beams on the 33-34th floors to fall and rest on the bottom flanges of their supporting girders.

Can fire destroy steel?

Photographs of structural steel deformed by fire are shown on page 3 of The Reinstatement of Fire Damaged Steel and Iron Framed Structures.

Steel loses strength when it's heated, and eventually fails, which is why it needs protection.

Fuel-based fires get hot unusually quickly.

Normal/natural fires usually spread slowly, and are limited by available ventilation.

What about the WTC specifically?

There are two explanations of how/why fire caused the WTC collapse here:

The latter reference contains an explanation for the collapse (in the side-bar, on the right):

First, in the absence of structural and insulation damage, a conventional fire substantially similar to or less intense than the fires encountered on September 11, 2001 likely would not have led to the collapse of a WTC tower. Second, the towers likely would not have collapsed under the combined effects of aircraft impact and the subsequent multi-floor fires encountered on September 11, 2001 if the insulation had not been widely dislodged or had been only minimally dislodged by aircraft impact.

It also says that they found no other causes:

Also, the investigation team neither found nor invoked any extraordinary events, beyond the terrorist attack that damaged the structure and removed the insulation, that led to the collapse of the towers.

The above (aircraft impact dislodging insulation) doesn't explain the collapse of Building 7. The analysis of the Building 7 collapse states that the failure of this building was more caused thermal expansion (steel changing size and shape): its fire-insulation wasn't affected by an airplane crash, but it failed in the 300°C-450°C temperature range, before it got hot enough (e.g. 650°C) for the steel to lose significant strength:

In the WTC 7 collapse, the loss of steel strength or stiffness was not as important as the thermal expansion of steel structures caused by heat.

There are various ways in which the WTC buildings and the WTC fire were famously unusual or unique.

The authorities learn from disasters and update the building codes and fire codes accordingly: perhaps that's another explanation for why we may not see an event quite this like one again.

  • Further details about the Building 7 collapse are allegedly available here: nist.gov/customcf/get_pdf.cfm?pub_id=861610 However that link is currently returning, "Due to a lapse in government funding, the National Institute of Standards and Technology (NIST) is closed and most NIST and affiliated web sites are unavailable until further notice." – ChrisW Oct 1 '13 at 21:26
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    Perhaps NIST has an analysis of the first two buildings, as they have for Building 7. – ChrisW Oct 2 '13 at 14:53
  • Thank You. I was pretty sure that if there were 10-20 skyscrapers collapsed just by fire and only 5-10 burned-out than my question was been closed. – apex_predator Nov 2 '13 at 19:03
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    FWIW, the WTC were most definitely not destroyed by a fire. They were destroyed by tons of jet fuel on fire combined with the huge amount of gravitational energy they had in their structure. – Sklivvz May 10 '14 at 0:50
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    "Partial collapses?" "Filler beams?" Those aren't even examples of collapse. Thats equivalent to picking some bark off a wooden house and claiming you caused a structural collapse. – D J Sims Mar 13 '16 at 8:38
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No steel building has collapsed from fire. The examples above are all "partial collapses", roof collapses, or something similar that is not a collapse of a steel building. You can find common attempts at counterexamples here:

http://911debunkers.blogspot.com/2011/06/other-collapses-in-perspective_04.html?m=1

WTC designers were aware of the absurdity of a 9/11-like scenario.

http://community.seattletimes.nwsource.com/archive/?date=19930227&slug=1687698

Lead WTC Structural Engineer John Skilling:

“We looked at every possible thing we could think of that could happen to the buildings, even to the extent of an airplane hitting the side… Our analysis indicated the biggest problem would be the fact that all the fuel (from the airplane) would dump into the building. There would be a horrendous fire. A lot of people would be killed. [But] the building structure would still be there.”

Some of the information contained in this post requires additional references. Please edit to add citations to reliable sources that support the assertions made here. Unsourced material may be disputed or deleted.

  • There has been extended discussion on this answer - the conversation has been moved to chat. – Oddthinking Mar 14 '16 at 11:39
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    "The Boeing 707 that was considered in the design of the towers was estimated to have a gross weight of 263,000 pounds and a flight speed of 180 mph as it approached an airport; the Boeing 767- 200ER aircraft that were used to attack the towers had an estimated gross weight of 274,000 pounds and flight speeds of 470 to 590 mph upon impact." books.google.com/… – DavePhD Mar 14 '16 at 21:21
  • @Dave PhD literally grasping at straws – D J Sims Mar 15 '16 at 1:44
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    @Mustang Kinetic Energy = (1/2)(mass)(velocity)^2 , so the kinetic energy of an equal mass plane traveling 540 mph versus 180 mph is 9 times greater. – DavePhD Mar 15 '16 at 13:02
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    Wrong nytimes.com/2003/12/03/nyregion/… – D J Sims Mar 26 '16 at 21:27

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protected by Oddthinking May 4 '16 at 1:42

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