Pool deck above the parking garage at the collapsed Florida condo building - a focal point of the forensic investigation - had cracks repaired back in 1996

• A construction permit shows Champlain Towers South Condo required "concrete structural repair."
• The work, in 1996, was conducted on the building's underground parking garage.
• At least 95 people have been confirmed dead following the June 24 collapse.

The condo building that collapsed last month outside Miami underwent a significant "concrete structural repair" in 1996 after 500 feet of cracks were discovered in the roof of its underground parking garage.

The garage - and the pool deck above it - have been at the center of the investigation into what happened on June 24, when the 12-story Champlain Towers South Condo building in Surfside, Florida, suffered a catastrophic failure. At least 95 people have been confirmed dead.

Residents long complained about flooding in the garage.

"There was always water in the garage," one told The Washington Post. "There was always water leaking."

Indeed, according to documents obtained by the Miami Herald, the building was known to have serious problems for decades.

In a March 1996 letter to the Surfside Building Department, an employee at the firm Western Waterproofing Company of America said the work would be conducted on the parking garage, which had suffered water damage.

The work shows "that they were having problems with water infiltration, which is saltwater infiltration, all these years," Abieyuwa Aghayere, a professor of structural engineering at Drexel University, told the Herald.

The extent of the damage would have been "atypical," he said, for a building that had been constructed in 1981.

A 2018 engineering report on the building warned that it showed signs of "major structural damage," including "abundant" cracking. Roughly 8% of the concrete slabs used in the garage and the building's plaza showed signs of "concrete deterioration," it said.