When a severe storm passed over a single-story restaurant, a roof collapse resulted. TSA was retained to determine the cause of the collapse. One of the most challenging parts of this type of investigation is distinguishing between distress that may be related to what actually caused the collapse and the rest of the damage which is a necessary result of the initial failure. TSA determined that the severe storm did not produce very extreme winds but was associated with very heavy rainfall over a short period of time.
Examining the structural framing, it was determined that someone had modified the structure to include a roof hatch, but they did not reinforce at the location where the roof hatch cut through structural elements. As a result, the roof failed prematurely around the hatch, and collapse of the back half of the roof resulted. The severity of the collapse was worsened by other construction defects, including not bracing the roof trusses properly.
