Federal investigators have released their preliminary findings into the collapse of the Champlain Towers South condo building in Surfside, Florida. As reported by The New York Times, the building’s pool deck contained a “severe structural deficiency,” with construction in some areas failing to meet both building codes and its original design parameters.

The investigation is being led by the National Institute of Standards and Technology and has so far included witness interviews, a review of historical records, tests on building materials, and the analysis of models for structural performance. The original design and construction of the building have been examined, as have any renovations and repairs in the years since. The potential for corrosion, ground settlement, and vibrations from nearby construction to contribute to the collapse has also been examined.

“In summaries of their preliminary findings ahead of a hearing Thursday, the investigators wrote that the pool deck’s design lacked sufficient strength at and between many of its supporting columns,” The Times reports. “The investigators determined that those problems were severe in many places.” 

According to The Times, the pool deck also contained steel reinforcement buried deeper in the concrete than initially designed, planters that were heavier and more extensive than originally designed, layers of sand and paving stones added at a later date, and signs of corrosion in some parts of the steel reinforcement.

A combination of these factors resulted in “critically low” margins between stability and collapse, according to investigators. The deck had previously shown signs of distress well before the collapse, including cracks in a planter and sagging concrete slabs, according to The Times. Officials do not anticipate completing their final report until May 2025.

98 people were killed when the condominium tower in the Miami suburb collapsed suddenly in the early morning of June 24th, 2021. Following the collapse of the tower, several questions have been raised about the condition of the building. One week after the collapse, a 2018 report resurfaced that warned of “major structural damage” at the base of the building, including a survey that identified a failing concrete slab on the pool deck and “abundant cracking and crumbling” to the underground parking garage.