Thread by @washingtonpost

In a split second, hundreds of lives changed forever. For many, the outcome hinged on a single number: their condo unit wapo.st/3xb1092

The Washington Post used property records, dispatch calls and interviews with survivors and relatives of the missing to learn who lived in the building and where they were at the time of the collapse. wapo.st/3xivGFh

Some survived because they weren’t in the building that night.

Others escaped with little more than the clothes on their backs. wapo.st/3xivGFh

The first to fall: 02s, 03s, 10s and 11s.

The middle section of the tower fell first. Experts said it appeared to crumble from the ground up.

The few people in those units who survived the collapse lived on the upper floors. wapo.st/3xivGFh

Three hours before the collapse, Estelle Hedaya, resident of Unit 604, wrapped up a phone call with her friend Debra Golan that lasted more than an hour.

Golan hung up with Hedaya at 10:25 p.m. Wednesday. It was the last anyone heard from her. wapo.st/3xivGFh

Cassondra Stratton, who lived in Unit 412, called her husband to describe what she thought was an earthquake tremor. Then the line went dead, her sister Ashley Dean said.

She's still missing. wapo.st/3xivGFh

As more than half of the building imploded, the west section somehow stood firm: units 05 through 09.

Residents from those units have told harrowing tales of the lengths they went to survive. wapo.st/3xivGFh

Along with Champlain Towers South, a community collapsed, neighbors who chatted on the beach and waved at each other from windows, people who shared a space they all called home. wapo.st/3xivGFh