South Florida

Four years after Surfside condo collapse, investigators zero in on design and construction flaws

Surfside condo tower Champlain Towers South collapsed on June 24, 2021, killing 98 people.
Surfside condo tower Champlain Towers South collapsed on June 24, 2021, killing 98 people. mocner@miamiherald.com

Four years after the collapse of Champlain Towers South killed 98 people in Surfside, investigators piecing together the rubble are homing in on shoddy construction as what most likely caused the 40-year-old beachfront condominium to fall at 1:22 a.m. on June 24, 2021.

“As we have shared in previous updates, there were many design and construction problems that weakened the building from the start,” investigator Judith Mitrani-Reiser said Monday in an update from the National Institute of Standards and Technology (NIST). “These deficiencies posed many potential failure initiation possibilities both in the pool deck and the tower....”

Most of the victims -- ranging in age from 1 to 92 years old -- were sleeping when two-thirds of the 12-story, 136-unit condo collapsed on a calm summer night. Retirees, elderly couples, newlyweds, transplants from New York and Latin America, young families, and a nanny who had left her home in Paraguay for the first time perished; in 501, three generations of the Cattarossi family died. Only three people survived atop the 40-foot pile of debris. No one was found alive after weeks of searching by rescue crews, but the remains of all victims were identified.

READ MORE: Remembering the victims of the Surfside tower collapse

Rescue and recovery teams worked around the clock at the site of Champlain Towers South catastrophe.
Rescue and recovery teams worked around the clock at the site of Champlain Towers South catastrophe. Al Diaz adiaz@miamiherald.com

Only four people living in the section of the building that fell and the security guard working the night shift in the lobby were able to escape during the seven-minute gap between the time the pool deck caved in and the middle and oceanfront sections of the tower came down. Iliana Monteagudo, awakened by creaking noises and a crack snaking down her bedroom wall, pounded on her deaf neighbor’s door to no avail, then ran down six flights of stairs shifting beneath her feet as the tower pancaked behind her.

Residents in the wing that stayed intact managed to get out but were not allowed to return to their homes, and the rest of the building, determined to be unstable, was demolished 10 days later as a hurricane threatened South Florida.

“Two clear questions coming out of this investigation are why the design and construction problems were not discovered when Champlain Towers South was built, and how do we evaluate the structural safety of existing buildings?” said Glenn Bell, co-lead investigator on NIST’s National Construction Safety Team. “These conditions existed from the time construction was complete, 40 years before the partial collapse.”

House of Cards: The Miami Herald investigation into the Surfside condo collapse

Greater Miami Jewish Federation President & CEO Jacob Solomon and Community Security Director Stephanie Viegas visit the memorial wall for victims of the partial collapse of Champlain Towers South in Surfside.
Greater Miami Jewish Federation President & CEO Jacob Solomon and Community Security Director Stephanie Viegas visit the memorial wall for victims of the partial collapse of Champlain Towers South in Surfside. Greater Miami Jewish Federation

The team is focusing on three “higher-likelihood” hypotheses out of its initial 12, each arising from construction flaws that doomed the building. The collapse could have been triggered by failure of a slab-column connection in the pool deck, where the structural design did not meet building code standards. Steel reinforcement was missing or misplaced and eaten away by corrosion. Heavy planters and pavers added years later to the poorly-draining deck increased the load on a support system “that was already functionally and structurally inadequate,” the report says.

Prolonged exposure to water in the parking garage, where residents had complained about flooding and ponding, corroded steel bars and degraded concrete in the basement columns that were not built to proper strength. Those brittle columns or the failure of a slab-beam-column joint in the southeast part of the tower, close to the pool deck, could have been the cause of the collapse.

Raquel Oliveira lost her husband, Alfredo Leone, and 5-year-old son, Lorenzo, in the Surfside condo collapse.
Raquel Oliveira lost her husband, Alfredo Leone, and 5-year-old son, Lorenzo, in the Surfside condo collapse. GoFundMe

“The fact that the pool deck collapsed before the tower does not preclude the possibility that there was some initiating event in the tower that set off the collapse of the very vulnerable pool deck,” Bell said.

A theory that the breaking off of the pool deck from the south basement wall could have started the collapse is now rated “lower likelihood” by investigators, as is the theory that sinking ground could have led to pile failure. Testing found that the limestone on which the foundation sat and the pile concrete were strong enough to support the building, and the basement slab showed no signs of cracking or sinking.

Surfside condominium collapse victim Edgar Gonzalez’s daughter, Tayler Scheinhaus, and his wife, Angela Gonzalez, hold hands as they arrive for his funeral in Palmetto Bay. Angela and daughter Deven suffered major injuries but survived.
Surfside condominium collapse victim Edgar Gonzalez’s daughter, Tayler Scheinhaus, and his wife, Angela Gonzalez, hold hands as they arrive for his funeral in Palmetto Bay. Angela and daughter Deven suffered major injuries but survived. Al Diaz adiaz@miamiherald.com

A 2021 Miami Herald investigation broached some of the same scenarios, with University of Washington engineering professor Dawn Lehman finding that skinny support columns that did not comply to code were clustered below the part of the structure that experienced progressive collapse. Given the design, “it’s amazing to me that something didn’t [fail] earlier,” she said.

Misplacement of rebar meant “all of the columns were cracking from day one,” local structural engineer Eugenio Santiago told the Herald.

Iliana Monteagudo, right, escaped by running down six flights of stairs as Champlain Towers South fell. Shamoka Furman, left, the security guard on duty, helped Monteagudo and others climb out of the parking garage.
Iliana Monteagudo, right, escaped by running down six flights of stairs as Champlain Towers South fell. Shamoka Furman, left, the security guard on duty, helped Monteagudo and others climb out of the parking garage. Courtesy

No records from the original construction have been found, hampering the investigation. The apparent lack of quality control in the Champlain Towers South case should be a red flag to engineers and builders, Mitrani-Reiser said, noting the importance of retaining initial drawings, quality assurance reports and peer reviews.

“This tragic event has revealed flaws in our systems, and quality is at the heart of it,” she said.

Elena Chavez, left, and Elena Blasser with their great grandson/grandson, John Rodriguez. Chavez, 87, and her daughter, Blasser, 64, died in the condo collapse in Surfside.
Elena Chavez, left, and Elena Blasser with their great grandson/grandson, John Rodriguez. Chavez, 87, and her daughter, Blasser, 64, died in the condo collapse in Surfside. Miami Herald archives

The principal investors, architects, engineers, contractors and Surfside officials involved in the construction of Champlain Towers are deceased. Developer Nathan Reiber, a Canadian lawyer who retired to South Florida and became a real estate mogul, died at age 86 in 2014 while living in a Star Island house.

The three-condo Champlain Towers complex was a huge development for the quiet, low-rise town of Surfside, populated 45 years ago mostly by retirees who could walk to the beach, synagogues and kosher delis. Reiber obtained exceptions to building department rules, in part by giving the town $200,000 so it could upgrade its sewer system and lift a construction moratorium. The project was stalled again when town staff suspected that the penthouse at the top of the south tower exceeded Surfside’s 12-story height limit. But the town council approved it. The south and north towers were completed in 1981, and the east tower, designed and built by different personnel using a different construction technology, was completed in 1994.

Alejandra Torres comforts Andrea Langesfeld, mother of Nicole Langesfeld, who died along with her husband Luis Sadovnic in the Surfside collapse.
Alejandra Torres comforts Andrea Langesfeld, mother of Nicole Langesfeld, who died along with her husband Luis Sadovnic in the Surfside collapse. Jose A Iglesias jiglesias@elnuevoherald.com

One year after the collapse, the $1.1 billion settlement of a class-action lawsuit was approved by Miami-Dade Circuit Court Judge Michael Hanzman. Wrongful death and personal injury payments ranged from $35 million to the family of one victim and $50,000 to some survivors. Securitas Security Services USA, which said in a deposition that the building’s alarm system was not activated the night of the collapse, paid nearly half the total. The condo association’s law firm and consulting engineer on its 40-year recertification, and developers and builders of the luxury condo next door, were among the three dozen defendants, who denied culpability.

Champlain South, once known as the “condo of the abuelas,” will be replaced by Dubai-based DAMAC International’s new “ultra luxury” condo, slated to open in 2029. The Delmore, designed by Zaha Hadid Architects, will feature 37 “mansions in the sky” starting at $15 million and served by residential butlers.

Steve Rosenthal, a Champlain Towers South survivor, at his temple. Rosenthal lost all his possessions save one item police found in the rubble: His cherished bar mitzvah bag containing his prayer shawl and tefillin.
Steve Rosenthal, a Champlain Towers South survivor, at his temple. Rosenthal lost all his possessions save one item police found in the rubble: His cherished bar mitzvah bag containing his prayer shawl and tefillin. Emily MIchot emichot@miamiherald.com

Plans for a memorial are the subject of contentious debate in Surfside

NIST’s final report is expected in 2026.

“We intend for our investigation of this failure to have a lasting impact, save future lives and ensure this never happens again,” Mitrani-Reiser said.

Dubai-based developer DAMAC International is building an ultra luxury “mansions in the sky” oceanfront condo where Champlain Towers South collapsed in 2021.
Dubai-based developer DAMAC International is building an ultra luxury “mansions in the sky” oceanfront condo where Champlain Towers South collapsed in 2021. DAMAC International; Town of Surfside
Collapse: Disaster in Surfside, is a podcast from Miami Herald/Treefort Media.
Collapse: Disaster in Surfside, is a podcast from Miami Herald/Treefort Media.

This story was originally published June 24, 2025 at 5:00 AM.

Linda Robertson
Miami Herald
Linda Robertson has written about a variety of compelling subjects during an award-winning career. As a sports columnist she covered 13 Olympics, Final Fours, World Cups, Wimbledon, Heat and Hurricanes, Super Bowls, Soul Bowls, Cuban defectors, LeBron James, Tiger Woods, Roger Federer, Lance Armstrong, Tonya Harding. She golfed with Donald Trump, fished with Jimmy Johnson, learned a magic trick from Muhammad Ali and partnered with Venus Williams to defeat Serena. She now chronicles our love-hate relationship with Miami, where she grew up.
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