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How Do You Chop 20 Stories Off a Too-Tall Building?

The building at 200 Amsterdam pokes up above the neighbors. (For now.) Photo: Gary Hershorn/Corbis via Getty Images

Now that the 52-story tower at 200 Amsterdam Avenue is almost done, it may soon have to be partly undone, like a construction film running in reverse. If the appeals court that will hear the case starting Wednesday upholds a judge’s ruling that the building is illegally tall, the crews now putting on the final touches will have to start unraveling the top 20 or so floors, breaking freshly installed glass, slicing through new steel beams, and grinding down recently poured concrete. If the never-used bathroom fixtures can’t be salvaged, they may have to be smashed, at considerable risk to the workers. “You break them, and they’re like razor blades,” says Bob Accardi, an executive vice-president at AECOM Tishman. “Glass, you expect to get cut from. Toilet bowls, not so much.” All that wastage has to be expelled and carted away. If the whole shebang were coming down, workers could run a rubble chute through the shaft to the basement, but here there will be actual working elevators in the way, so the chutes will have to be fastened to the still unscuffed exterior.

The building sits on a bizarre knot of different parcels, and figuring out which rules apply has been an oracular exercise even by the standards of New York’s inscrutable zoning code. Complexity favors developers equipped with expensive legal advice, which is how  SJP Properties persuaded the Department of Buildings to issue a permit for a 668-foot spear sticking into the flank of the Upper West Side. The narrow, stretched-out tower designed by Elkus Manfredi reaches its kinda–sorta–neo–Art Deco–ish crown via a series of setbacks that make it look like a staircase in the wrong aspect ratio. Any tall building can unleash the usual It’s out of character! versus More housing now! shoutfest, but this one has turned area residents into self-appointed land-use experts. If you walk up Broadway and overhear someone saying “gerrymandered lot,” chances are they’re talking about 200 Amsterdam rather than congressional districts.

If the ruling stands, Upper West Siders will witness a slow-motion decapitation from the inside out, which is about as gruesome as it sounds. “Taking down a building is more surgical than erecting one,” says Jay Badame, the president of construction management at the engineering firm AECOM. “It’s become an art and a science combined.”

The unbuilding of skyscrapers happens regularly in New York, and even lopping the top off isn’t unprecedented. The same fate befell 108 East 96th Street in 1991, when developers agreed out of court to slice 12 illegal floors off a 31-story tower while it was still under construction. And truncating 200 Amsterdam is a relatively routine operation when compared to the razing of the 700-foot Union Carbide Building at 270 Park Avenue, eventually to be replaced by a 1,200-foot headquarters for JP Morgan. In a city too packed for implosion or wrecking balls, disassembling an entire structure is slow and dangerous work, planned by specialized engineers. (Excising one part, even as residents are moving into the rest, gives the process an extra layer of delicacy.) When the building is going up, a crane hoists equipment and materials into place as they’re needed, often directly from the back of a flatbed truck. When it’s coming down, though, you need someplace to toss all the rubble, and piling the detritus of too many discarded stories on the floor below can get you into structural trouble.

So can yanking out a length of steel without the proper preparation. “As you’re deconstructing the building, you’re also bracing it, so you don’t leave something freestanding that can topple over,” says the Department of Buildings first deputy commissioner Gus Sirakis. It’s an elaborate puzzle that can involve as much building as breakage: shoring up floors, supporting steel skeletons, erecting scaffolding, installing chutes, and positioning cranes. Sirakis reviews the options for avoiding collapse, sounding like he’s planning a military operation. “You can sling a beam to the crane while it’s being cut. You might have an iron worker doing the torch cutting but it’s not the same as bolting up your spandrel beam in place. You might have to pull exterior frame inward as you cut it. Sometimes you do the demolition with a grappling arm, cut and grip the [structural] member at the same time.”

As is often the case, disaster helped write the procedures. In 2007, a fire broke out near the top of the Deutsche Bank building on Liberty Street, which had been irreparably damaged on 9/11 and was being torn down. The firefighters who responded discovered that workers had disabled the sprinkler system and the standpipe, laid wooden platforms over one staircase, and partially demolished another. Two firefighters were killed and dozens were injured. The city revised its regulations, requiring safety systems to remain functional even as the structure around them dissolves.

As with everything about living in New York, tight quarters make everything more complicated. At 270 Park, there was nowhere to plant a tower crane at ground level, so Tishman, the company running the project, built a temporary structural balcony onto the doomed tower. It’s like giving your executioner a piggyback ride so he can reach your throat.

How Do You Chop 20 Stories Off a Too-Tall Building?