NEW YORK (CBSNewYork) — Crews secured the site of a four-story Brooklyn brownstone Monday evening after it partially collapsed the night before.

It came on the heels of the painstaking work needed to dismantle the condemned building piece by piece.  The structure will be loaded with demolition set for Tuesday morning.

The side of 241 Carroll St., came crumbling down around 1:30 a.m. Monday with a family of six sleeping on the top floor, including three children, ages 8, 6 and an infant, CBS 2’s Kathryn Brown reported.

The building houses 14 people, most of whom were on vacation, including a family whose apartment took the brunt of the collapse.

“Most of it collapsed into the children’s bunk beds on the first floor. So they were very, very fortunate that they were on vacation,” FDNY Dept Asst. Chief James Leonard told reporters, including CBS 2’s Sean Hennessey.

Officials with the Office of Emergency Management, NYPD, FDNY and Department of Buildings all responded to the scene.

Scott Lehr, who lives behind the building, said he heard a loud bang from his bedroom window.

“I went outside and I saw a big chunk of the roof fall down,” Lehr said.

He said he grabbed his wife and two kids and rushed to the front of his home where they were evacuated by firefighters.

“I was actually sitting on my front porch and heard a loud bang,” neighbor Mike Candoniero told CBS 2’s John Slattery.

carroll gardens collapse Carroll Gardens Brownstone To Be Demolished After Walls Collapse

Carroll Gardens Wall Collapse (credit: CBS 2)

Fire officials said it’s incredibly fortunate that most of the residents of the apartment were not at home.

“There was one family on the top floor, five people were home and were able to evacuate the building without injury to themselves,” Deputy Asst. Chief James Leonard of the FDNY told Slattery.

The owners of the partially collapsed building — Howard and Sisi Schneider — live on the bottom floor with their two daughters, but they were vacationing at Bear Mountain on Sunday night, Brown reported.

They raced back home when they got the call. The Schneiders, who have owned the building for nine years, said the home was constructed in the 1840s.

Months ago, they noticed a hairline crack in the wall and said they had just contracted with a construction company to start repair work but nothing had been done yet, Brown reported.

“Wood rots, the mortar between the bricks just gets old and starts to fall apart,” Leonard said. “And we have gravity that will bring the building down eventually.”

“It’s a blessing that everyone’s okay,” Sisi Schneider said.

Building inspectors said the row home used to be a middle unit rather than an end unit but added adjacent units were demolished years ago to make way for a school.

Since the units are designed to structurally interlock some now wonder if that change years ago made this building vulnerable.

“I was speaking to a former resident this morning who moved out because there were a lot of structural problems in the building, so she was pretty convinced that it was not a safe place to live,” evacuee Becky Morrison said.

Four adjoining buildings were also evacuated as a precaution.

The American Red Cross said 21 adults and six children have met with volunteers. So far, a family of six — two adults and four children — has been given emergency housing and funds for food and clothing.

“They couldn’t retrieve anything whatsoever,” senior responder Mauricio Serrato said. “They were able to just come out with whatever they had and what they came out with was nothing but their PJs, not even shoes. They didn’t have a chance to grab anything.”

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