Design flaw blamed for fall of school roof

The roof collapse at Farrington High School’s auditorium is believed to have been caused by a design failure dating back to the building’s original construction 58 years ago, according to a preliminary report.

Structural engineers hired by the Department of Education to determine how the roof came down — and whether other buildings may also be at risk — concluded that maintenance, the age of the building and condition of the roof did not appear to be factors in the collapse Nov. 23, said Ray L’Heureux, Department of Education assistant superintendent for facilities and school support services.

Repairs and upgrades to the building also were not factors.

The culprit instead was a steel roof truss whose "design limit" was overextended by an attached concrete cantilevered balcony that provided access to lights used to illuminate the stage, L’Heureux said Monday.

The truss that failed was the second from the stage.

"It was a time bomb just ticking," L’Heureux said. "This thing was designed to fail the minute it was built."

He said the light balcony almost doubled the vertical load that the truss had to support.

A 40-foot section of the auditorium’s roof fell during a short but heavy afternoon rainstorm.

The engineers report said the rain also wasn’t to blame, though vibrations during the downpour could have been the "last straw," L’Heureux said.

"This thing could have fallen in 1961, in 1983," he said.

L’Heureux discussed the findings of the preliminary report, which will be released later this week.

He added that the design flaw would be impossible to see in a regular inspection designed to determine whether roof or truss maintenance is needed.

In the wake of the finding, the DOE is reviewing its buildings to determine whether any others were designed or built by the same companies that put up Farrington’s auditorium. None have been found so far.

The DOE has already pledged to inspect nine auditoriums built around the same time as the one at Farrington High.

Meanwhile, officials still did not have an estimate for damage.

But L’Heureux said engineering firm Kai Hawaii did find the auditorium was otherwise "structurally sound" and so could be saved rather than torn down. That’s a bit of good news for the DOE: The cost of repairs to the building is in the neighborhood of $8 million, L’Heureux said, while rebuilding it would cost $30 million.

"It’s a no-brainer," he said.

No one was injured in the roof collapse of the 1,100-seat auditorium, but it was a close call. Just hours later, 100 to 200 people were scheduled to be in the auditorium for a slam poetry contest.

Since the collapse, crews have been removing debris from the auditorium. That work is expected to wrap up soon, but it’s unclear when the DOE will be able to secure the funding for repairs.