An East Village rooftop party that ended last night with one reveler rushed to Bellevue Hospital in critical condition and the remaining guests stranded on the roof did not actually involve a roof collapse (though you'd be forgiven for thinking so if you read the New York Post). The part of the building that collapsed was the stairwell, where one man "fell through four half-landings, or two stories." He was on his way out of the party at about 1:30 a.m., NBC New York reports. So the 30 to 40 people still on the roof didn't apparently cause the collapse, but rather some still-undetermined factor as this guy used the stairs.
The rest of the guests had to be rescued from the roof by firefighters with aerial buckets, though a few managed to climb into a top-floor apartment and out onto the fire escape, and descend the seven-story building that way. The stairway eventually got patched up with "planks and boards," according to the Post, and the building is still considered habitable. But the whole episode does not instill confidence for those of us who live in old walk-ups.