McCormick Place — Unprotected Steel Roof Trusses Sagged and the Hall Came Down

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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