The Hyatt Regency Hotel was approximately a year old at the time of the collapse. Unknown to anyone, the walkways were seriously defective and were on the verge of collapse from the time of initial construction. The walkways at the second and fourth floors were 8 ft wide and 120 ft long and suspended by slender hanger rods from the roof structure, creating the impression of thin, ribbon-like structures floating in space.
SGH determined that two errors led to the failure: the design of the hanger rod/box beam connections was grossly flawed and a change in the hanger rod arrangement during construction doubled the load that the flawed connections were required to bear. We attributed the errors to a widespread breakdown in communication and quality procedures during design and construction. We also concluded the associated parties missed many opportunities to avert the failure.