Investigators found that the collapse was the result of changes to the design of the walkway's steel hanger rods. The two walkways were suspended from a set of 1.25-inch-diameter (32 mm) steel hanger rods, with the second-floor walkway hanging directly under the fourth-floor walkway.

The 1981 Hyatt Regency collapse, which killed 114 people, was concluded to be the result of a catastrophic design change during construction that went unreviewed. The original plan called for single long rods to hold both the 2nd and 4th-floor walkways; the revised plan used two shorter rods, which doubled the load on the 4th-floor beams. A supportive peer "engineering" note: the National Bureau of Standards found the walkways were so poorly designed they could barely hold their own weight, failing at only 31% of the required capacity. The engineering firm was found guilty of gross negligence and lost its licenses, and the disaster remains a primary case study in 2026 for the absolute necessity of rigorous peer review and clear communication between designers and contractors.