Feature

Faulty Towers

Landmark towers may not be immune to failure, but boring, ubiquitous buildings, the ones we take for granted, often cause the most trouble. Before 540 Madison came along, one of the most troubled buildings in New York was the Vermeer, a 1964 co-op at Seventh Avenue and 14th Street. Six years ago, its original layer of white glazed brick had to be completely removed and replaced. Though nothing tumbled to the street, the façade was bulging conspicuously. The reason is that the concrete that forms the building’s frame tends to shrink, while brick walls remain constant. Restoration architect Walter Melvin discovered that the steel angles that were supposed to support the brick wall and lock it to the frame had either shifted, because of the shrinkage, or were missing altogether. This meant that the brick wall was only loosely attached to the building and was beginning to crumble under its own weight, crushing the ground-level storefronts. Architects and engineers say this is a very common situation for buildings of this era.

“We’re just working through every building built in New York in that time period,” says Melvin. “There are no movement joints whatsoever in the buildings. The concrete frames shrink, crushing the brick on the outside and disconnecting the wedge anchors that hold the brick shelves on the side of the building. And then they had the problem where they didn’t have enough anchors in anyway. Every one that I’ve opened up has had too few anchors.” So if you look carefully at any glazed-brick building surrounded by a sidewalk shed -- and there are plenty of them -- you will see bulging spots, cracks, and, occasionally, sections of the siding pulling away from the façade.

Here’s an unsettling idea: Besides the fact that a shoddy construction job or a poorly thought-out design can sit quietly for decades and then one day, like a volcano, erupt, our knowledge about the design and construction of buildings isn’t cumulative. We don’t exactly learn from our mistakes, because the technology keeps changing.

Buildings, especially in the postwar era, especially signature skyscrapers, are experiments, one-offs. While the brick-and-tie method of building is positively anachronistic -- colonial architecture in the sky -- more technologically assertive methods of building design and construction are also problematic. Signature buildings of every decade have pushed the envelope of engineering knowledge and construction techniques, and the most elaborate designs can be undone by very small things. As the space-shuttle Challenger explosion could be pinned on faulty O-rings, problems with big glass office towers can often be attributed to sealants. Glass office towers, mighty statements of corporate and architectural power, have to be caulked, like bathtubs, or they’ll leak.

“It’s the archenemy, water,” says Kaese.

“Water is the single most destructive thing, even sitting there doing nothing, just being water,” adds architect Page Ayres Cowley of the Cowley Duenow Partnership.

Water proved to be the undoing of one of New York’s most significant architectural landmarks. Lever House, the 1953 Skidmore, Owings and Merrill building, began the city’s romance with the glass-curtain wall. “The architects’ design was to make it almost a prism, so that it almost floats,” notes Alex Herrera, director of preservation at the city’s Landmarks Preservation Commission. “They designed it with the best technology they had available at the time.”

Unfortunately, while the building has gleaming stainless steel framing the glass on the exterior, the steel inside, the lattice that actually supports the glass, was not stainless. And because the sealants, made of a linseed-oil-based putty -- state-of-the-art, 1953 -- failed, the steel structure of the curtain wall rusted. The rust caused the steel to expand, dislodging or breaking many of the building’s glass panels. For years, maintenance crews replaced glass panels whenever they broke. SOM has devised a plan to rescue Lever House that involves re-skinning the whole building and replacing the rusty steel with stainless.

The architects and engineers who inspect façades for structural flaws are like the oncologists of the building trades, telling us things we don’t really want to hear. Kaese, who is currently finishing up the restoration of the Whitney Museum’s façade, mentions a trait of the World Trade Center’s that is less overtly frightening but still unnerving: “If you sit on the east side in the morning when the sun hits the building,” she says, “you can hear the whole thing pop. You can hear the movement of the structure.”

She then points out that this is true of any building “if it’s quiet enough.” Buildings, like people, harbor little idiosyncrasies and pathologies that occasionally cause them to behave destructively, dumping a ton of bricks onto Madison Avenue during peak holiday-shopping season, say, or caving in on 42nd Street just as New Year’s Eve approaches. And rainy spells bring out the worst in buildings. This winter’s parade of northeasters has turned some masonry façades into cottage cheese.

Friedman, for his part, is marginally reassuring. “Nothing collapses,” he says, “until a lot of things are wrong simultaneously. It takes a lot for brick to actually start falling off a building.”

And if that is not comforting enough, Friedman adds that a building on the verge of collapse will likely issue some sort of warning. “Before everything falls down, there are a lot of ugly noises,” he says. “There’ll be a rain of mortar before the bricks themselves actually start falling out, so it’s like, ‘Why am I getting pelted by sand?’ That would be your first reaction.”

And your second reaction? What should you do if you’re walking down the street and you feel a trickle of sand falling on your head?

Friedman, the structural engineer, offers a pragmatic answer: “Run.”