The “sudden failure” of an Orange County apartment complex hastily evacuated last week could stem from problems in the ground beneath it, its foundation or the five-story structure itself, but getting residents out quickly made sense, experts say.
The issue at The Rialto apartments on Sand Lake Road looks to be a building failure caused by “differential settlement,” the uneven sinking of different parts of a building, said Kamal Tawfiq, a professor at the FAMU-FSU College of Engineering in Tallahassee.
The problems seem to have appeared rapidly and are unusual enough that he is already talking about the incident with his students, he added.
The apartment was evacuated Thursday morning after a frantic resident called 911 to report her front door wouldn’t open and she heard “popping” noises, officials said. Firefighters had to break down that woman’s door and the doors in several other apartments to help residents leave.
Items are removed from apartments at The Rialto apartments in Orlando on Tuesday, March 24, 2026. The Rialto apartments building had to be evacuated Thursday, March 19, after signs of structural instability were found. Residents are still unable to return. (Stephen M. Dowell/Orlando Sentinel)
Later, inspectors found signs of “structural instability,” including cracks around several doors, and ordered all 358 residents to evacuate. The residents remain locked out while an engineering firm hired by the complex investigates. Inspectors arrived last week and are still investigating the cause and extent of the problems, county officials said.
Orange’s building safety department says two projects were done at the complex without proper permits, but it wasn’t clear they played any role in what happened.
The resident’s call to 911 about “popping” sounds may have indicated something inside the structure giving way, Tawfiq said.
That could happen “if there is a void that collapses, or a sinkhole, underneath the foundation,” he said. “Or it could be actually in the structure due to corrosion with time, and the structure has been weakened until it gets to the level that it didn’t handle the stresses…and collapsed.”
Residents gather and remove some items from their apartments at The Rialto apartments in Orlando on Tuesday, March 24, 2026. The Rialto apartments building had to be evacuated Thursday, March 19, after signs of structural instability were found. Residents are still unable to return. (Stephen M. Dowell/Orlando Sentinel)
Necati Catbas, an engineering professor at the University of Central Florida, said he was surprised by what happened given that The Rialto, which county records says was built in 2014, is a relatively new building.
But based on what he has heard in the news, he concurred with Tawfiq that differential settlement was a likely culprit and that the “popping” noises were caused by excessive forces placed upon parts of the structure.
The apartment’s location between Spring Lake and Little Sand Lake may have been a factor, too.
“It’s right like at a very narrow point between these two relatively larger lakes,” Catbas said. “Being so close to these water levels…these buildings might have experienced some settlement, and especially with differential settlement…that’s when you start seeing cracks.”
Rialto advertises itself as “one of Orlando’s premier residential experiences” that “offers homes with sweeping views of Spring Lake and high-end amenities.”
One of the now-closed businesses attached to The Rialto apartments in Orlando is pictured on Tuesday, March 24, 2026. The Rialto apartments building had to be evacuated Thursday, March 19, after signs of structural instability were found. Residents are still unable to return. (Stephen M. Dowell/Orlando Sentinel)
The county’s report issued Monday noted the complex is in violation of the state building codes or county ordinances since it did not have required permits or inspections on two projects.
Those two projects, the report said, were “stucco repairs” to the exterior of the building and the construction of a retaining wall near its dog park.
Catbas said he could not comment on whether those could have contributed to the building’s problems without knowing more about the work.
“We have to learn a little bit more about those in terms of locations and whether those are structural elements that might lead to these types of problems,” he said.
Northland Investment Corporation, a Massachusetts-based real estate private equity firm, owns the complex. The firm didn’t immediately respond to a request for comment Wednesday.
The company is paying its evacuated residents $1,000 each to help with moving costs and is not charging them rent for the days they cannot live in the building, a spokesperson said earlier this week.