Cause of 4-alarm fire at South Austin buildings unlikely to be determined, official says

The cause of a Wednesday fire that spread from an empty building to the nearby, occupied Casulo Hotel might remain "undetermined" due to the extensive nature of the damage, an Austin fire official told the American-Statesman.

Firefighters initially classified the fire as a two-alarm fire but later upgraded it to a four-alarm event. A fifth alarm is the highest level of severity for a fire, Austin Fire Department spokesperson Rachael Lewis said. The number of alarms dictates how many additional units and resources are sent to combat a fire.

It took more than five hours for firefighters to get the fire under control, and they were still working to extinguish hot spots Thursday morning, Lewis said. Firefighters were finishing up work Thursday afternoon.

The vacant building where the fire originated was completely destroyed, The Casulo Hotel's interior appeared to be completely gone, and cracks could be seen in the building's exterior. Multiple floors collapsed in the hotel, and the building was unstable.

One firefighter was the only person injured, the Austin Fire Department said in a post Wednesday night on X, formerly Twitter. Thayer Smith, acting assistant fire chief, said in an email the firefighter received a "small second-degree" burn on the back of the hand. Smith said he was treated at a minor emergency center.

Pete Constantine, a battalion chief who was on the scene Thursday, told the Statesman that he believed investigators are finished trying to determine the cause.

To determine a fire's cause, investigators interview witnesses and examine where the fire originated. But the building where Wednesday's fire started is nothing but burned rubble.

"There's a lot of things that go into determining a fire," Constantine said. "So when you have that extent of damage, it's hard to say that 'this was the cause.'"

Constantine added that buildings under renovation, such as this one, are generally most susceptible to fires because the building isn't complete. This means there are often holes in the walls and floors, and the fire can get into those voids and spread quickly, he said.

Just before 2 p.m. on Thursday, firefighters could still be seen checking for hotspots with a drone in the hotel, and on the ground of the completely destroyed vacant building.

Timeline of the fire

Austin Fire Assistant Chief Andre de la Reza said the Fire Department received calls about the fire at a three-story building around 2:10 p.m. Firefighters arrived and found the fire in the upper floors of an empty building behind the hotel that was under renovation.

About 10 minutes later, de la Reza said, the fire at the empty building was upgraded to a two-alarm fire. He said firefighters upgraded the alarm level due to the collapse of the second floor in that building and due to the high winds possibly threatening an apartment complex to the east of the building.

De la Reza said embers were spotted in the gutters of that apartment complex, but that the fires never grew to cause any type of damage.

Due to the expanding nature of the fire, it was upgraded to a third alarm at about 2:30, he said.

Just before 3 p.m., the fire had spread to the Casulo Hotel and the fire was upgraded to a four-alarm fire.

Firefighters were in "defensive" mode to put out the fire. This means they spray water onto the fire from the outside and do not go inside because of the size of the fire.

A hotel employee who asked not to be named said there were 12 people staying at the hotel at the time of the fire.

De la Reza said firefighters began evacuating the hotel, and due to the location of the fire in the upper floors of the hotel, firefighters remained in a defensive capacity.

De la Reza said arson investigators were at the scene, which is normal for an incident of this size.

Chris Bernal was working from his South Austin home when he caught a glimpse of smoke rising from the empty building next door. Realizing it was a "real fire," he and his wife started gathering up their cats to leave.

The building was completely engulfed in flames by the time firefighters arrived, Bernal said, describing the sight as "one big fireball."

"You couldn't even see the original building," Bernal said. "At that point, it was just smoke and fire. … As soon as I stepped out my door, (I) could feel the heat from the fire."

Staff writer Bianca Moreno-Paz contributed reporting.

This article originally appeared on Austin American-Statesman: Cause of 4-alarm fire at South Austin buildings may not be determined