McCormick Place — Unprotected Steel Roof Trusses Sagged and the Hall Came Down
Summary
McCormick Place, Chicago's flagship lakefront exhibition hall, was destroyed in the early hours of 16 January 1967 when a fire that began in a trade-show booth weakened its unprotected long-span steel roof trusses and brought the main hall down within roughly an hour, killing one man — security guard Kenneth Goodman, 31, who could not find an unlocked exit. The proximate cause was not the size of the fire but the bare metal over it: the great trusses that spanned 210 feet between columns and cantilevered 80 feet at each end carried no fire-resistive coating, so heat from the burning exhibits softened them, they sagged, and the roof collapsed onto the floor.
The building had been widely regarded as fireproof. Insurers and the public alike treated its steel-and-concrete construction as proof against exactly this outcome, and the main floor had been left without an automatic sprinkler system on the theory that the ceiling was too high for sprinklers to be effective. The hall was packed for the National Housewares Manufacturers Association show — roughly 1,250 booths of appliances, packaging, plastics and display material — an extreme combustible fire load across an open, undivided floor with no fire walls to check it.
The fire, attributed to temporary electrical wiring behind a booth, was reported by janitors around 2 a.m. With no sprinklers, no compartmentation, and four of the building's seven hydrants shut off for nearby Lake Shore Drive construction, it grew unchecked while firefighters drafted water from Lake Michigan a quarter-mile away. The unprotected trusses reached failure temperatures before crews could mount an effective attack.
The investigation, led by Rolf H. Jensen, professor of fire protection engineering at the Illinois Institute of Technology, found a structure that could not have survived the fire regardless of severity: bare long-span steel, no sprinklers, no fire walls, a disabled water supply, and a fuel load no one had matched against the building's actual fire resistance. McCormick Place became one of American fire protection's defining cases — the fire that helped push sprinklers, fire-coated steel and smoke-and-heat venting toward the standard, and that was rebuilt with some 40,000 sprinkler heads where it had stood with none.
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Timeline
The Build: A Column-Free Hall Roofed With Bare Steel
McCormick Place was conceived as a statement of Chicago's primacy as a convention city. Opened in November 1960 to designs by Alfred Shaw of Shaw, Metz & Associates, it offered exhibitors an enormous, column-free main floor under a clear-span roof. That clear span was the building's engineering signature and, in the end, its fatal feature. The roof was carried on long-span steel trusses reaching 210 feet between columns and cantilevering a further 80 feet at each end — an ambitious structure that put a great deal of unbroken roof on a small number of slender, deep steel members.
Those members were erected bare, with no sprayed fire-resistive coating and no encasement. The omission was not seen as a deficiency at the time, because the building was understood — by its owners, the public, and the insurers who wrote tens of millions of dollars of coverage on it — to be fireproof by virtue of being built of steel and concrete. That belief conflated incombustibility with fire resistance. Steel does not burn, but it does not need to: it loses stiffness and strength as it heats, and a long-span truss carrying a large tributary roof area on slender members is among the structural forms most sensitive to that loss.
The same confidence shaped the building's protection. The principal floor was left without sprinklers, on the theory that the roof was too high for them to reach a fire effectively, and had no fire walls to divide it into smaller fire areas. Into this single, undivided, unsprinklered, bare-steel-roofed volume the National Housewares Manufacturers Association show packed roughly 1,250 booths of appliances, plastics, packaging and display structures — a heavy, continuous combustible fire load. The building had become one immense fire compartment, full of fuel, roofed by metal that nothing protected.
The Failure: How a Booth Fire Took Down a Roof
The fire was reported around 2 a.m. on 16 January 1967, when janitors saw smoke behind an exhibitor booth; the cause was attributed to temporary electrical wiring. With no sprinklers over the floor and no fire walls to contain it, the fire spread laterally across the booths, feeding on the housewares fire load, and within about half an hour had grown enough to bring a fifth alarm.
The fire department's problem was compounded by water. Four of the building's seven hydrants had been shut off for nearby Lake Shore Drive construction, and others were frozen in the sub-zero cold. Companies and fireboats were forced to draft from Lake Michigan and run lines from working hydrants as much as a quarter-mile away — a delayed, under-supplied attack on a fire already large and accelerating.
The collapse mechanism was conventional for unprotected long-span steel. The steel did not melt; it merely got hot. As the exhibit fire drove temperatures up across the open floor, the bare trusses lost stiffness and strength, deflected under their own weight and the roof loads, and sagged. A long-span truss that softens has no reserve: there is no shorter alternate path for a 210-foot clear span, and the cantilevered ends magnify any loss of restraint. Within roughly an hour of ignition the weakened roof collapsed onto the exhibition floor. The building, thought fireproof, had been gutted and brought down by a fire that began in a single booth. One man died — security guard Kenneth Goodman, 31, who could not reach an unlocked exit in time.
The Reckoning: A Building That Could Not Have Survived
The post-fire investigation, led by Rolf H. Jensen, professor of fire protection engineering at the Illinois Institute of Technology, left little room for the language of accident. The team found that the structure was unable to withstand the fire regardless of its severity — that the loss was not the product of an unusually ferocious blaze but of a building operated without the defenses such a fire demanded.
The deficiencies were layered and each independently grave. The long-span roof steel was unprotected, so a sustained fire was sufficient to disable it. The main floor had no sprinklers, removing the one system designed to control a fire while it was small, and no fire walls, so a booth fire had the run of the entire hall. The water supply that should have backstopped manual firefighting had been hollowed out — four of seven hydrants shut off in a cold that disabled still more. Against an extreme fuel load, every layer that might have caught the failure had been removed or omitted in advance.
The forensic lesson was a category error as much as a connection detail. McCormick Place was "fireproof" only in that its frame would not itself ignite; it was acutely vulnerable in the sense that mattered, the retention of structural capacity in fire. The case demonstrated, in the most public possible venue, that incombustible construction is not fire-resistant construction, that a high ceiling is a reason to engineer suppression rather than omit it, and that an unprotected long-span roof over a heavy fuel load is a collapse waiting for an ignition source.
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Contributing Factors
Aftermath
The McCormick Place fire killed one man, security guard Kenneth Goodman, and destroyed a structure the public and its insurers had treated as effectively fireproof; housewares exhibitors alone lost an estimated 25 million dollars in merchandise and displays. The Jensen investigation found the building could not have survived the fire under any severity, and the case became a touchstone of American fire protection engineering. It accelerated a cluster of code and standards changes that hardened later exhibition and industrial buildings: fire coating of structural steel framing, far wider use of automatic sprinklers including over high-piled and high-ceiling spaces, automatic fire doors, and the development of NFPA 204, the standard for smoke and heat venting; the Chicago Municipal Code was revised on exhibition halls, electrical installations, exits, fire walls, and venting. McCormick Place was rebuilt under Gene Summers of C. F. Murphy Associates and reopened on 3 January 1971 with fire-protected steel and on the order of 40,000 sprinkler heads — built explicitly against the failure the original had embodied. In the literature it became a byword for a single lesson stated plainly: incombustible is not fireproof, and a bare long-span roof over an unsprinklered fuel load is a collapse with a date not yet filled in.
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Lessons
- Never confuse incombustible construction with fire-resistant construction — steel that cannot burn still loses its strength in fire; protect the load path or assume it will fail when the fire is large enough.
- Treat a long-span roof as the most fire-sensitive element in the building — slender members carrying large tributary areas have no alternate path, so fire-coat them and never run a heavy fuel load beneath bare long-span steel.
- Reject the high-ceiling excuse for omitting sprinklers — a tall space is a reason to engineer suppression and venting for the height, not a license to leave a combustible occupancy unprotected.
- Match a building's fire defenses to its actual contents, not its assumed reputation — a hall packed with 1,250 booths of plastics and appliances is a different, far more dangerous building than the empty shell that was approved.
- Protect the water supply as part of the fire-protection system — disabled hydrants and a degraded supply remove the last line of defense exactly when manual firefighting must hold the line. ---
References
- McCormick Place Wikipedia
- Rebuilt, but never forgotten – the McCormick Place fire of 1967 Exhibit City News
- The January 16, 1967 McCormick Place Fire, Chicago, Illinois Digital Research Library of Illinois History Journal
- NFPA Journal Recounts McCormick Place's Fiery History Occupational Health & Safety (NFPA Journal)
- Conventions: The Cost of the New Chicago Fire TIME