Federal investigators have discovered that the deadly Surfside condo collapse that occurred in 2021 actually started weeks before a portion of the building came crashing down.
The National Institute of Standards and Technology (NIST) said the first structural failure at the Champlain Towers South happened at two garage column connections beneath the pool deck in early June 2021.
That issue created a domino effect, the Wall Street Journal said, that went undetected for 21 days until the collapse. As the columns failed, the pool deck concrete slab warped and fractured, shifting the deck’s weight to other columns.
There were reports of a sliding glass door popping from its frame, shifting entry gates that were jammed shut and water leaking through the garage ceiling.
“When building structures are designed and built to required codes and standards, they have margins against failure, meaning they should be able to support much more load than they are expected to bear,” investigator Judith Mitrani-Reiser, said, according to The Associated Press. “In the case of Champlain Towers South, however, these margins against failure were too narrow from the start.”
The pool deck gave way on June 24, killing 98 people in the collapse. The building came down at about 1:22 a.m. local time as many inside were sleeping.
The agency said that the failures came from the complex’s original design, which did not meet codes and standards 40 years ago. In the 1990s, heavy landscape planters and thick paving stones were added to the pool deck, increasing the building’s weight. The NIST said the added weight, along with corrosion-related degradation, caused the collapse.
Hours before the collapse, a planter had detached from the wall, the AP reported. The water flowing from the garage ceiling looked like a “water faucet,” one person told investigators.
The NIST said it was one of the most complex investigations into a building’s failure, with investigators examining two dozen possible causes, The New York Times reported.
The details were released in a NIST report into the tragedy, days before the five-year anniversary of the collapse.
The final report is still being prepared, which will contain more evidence. The report released this week did not include safety recommendations, The New York Times reported.
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