When bricks peeled off the side of 540 Madison Avenue and tumbled to the pavement last December, the office tower was portrayed in the press as an architectural Bad Seed, a building destined to wreak havoc from the moment it was born. Though the southern façade of 540 Madison gave way only after workers hired by the new owner, Harry Macklowe, punched windows into a previously unbroken expanse of brick, blame was heaped on the negligence of the contractors who erected the tower in the late sixties. They had left out two thirds of what shouldve been 14,500 brick ties, strips of corrugated metal that anchor the thin brick exterior wall to the layer of cinder block that sits snugly on the buildings frame.
Certainly, 540 Madison represents a worst-case scenario, but its troubles are not unique. The buildings deficiencies are rooted in the fact that modern architecture allows only a thin margin of error. Our faith in structural engineering and computer simulations has led to a lack of redundancy. Thats the phrase used by architectural engineers Matthys P. Levy and the late Mario Salvadori in their book Why Buildings Fall Down to explain disasters such as the 1979 collapse of the Kemper Arena in Kansas City, triggered by rain, wind, and miscalculation.
Generally, when we think of buildings being dangerous, we think of old ones, all covered with parapets, balustrades, and gargoyles. But many of these structures are in fact much stronger than newer ones. Structural engineer Donald Friedman, author of Historical Building Construction, tells a story about working on a 1917 office building in lower Manhattan that was supported by steel columns clad in brick. We opened up a column, and there was no column there, Friedman recalls. There was a hollow space in the brick pier in the shape of the column, and a little red staining on the brick where there was rust. But the column was gone. It had rusted to the point where it was gone. For four stories, from the roof down, there was no column worth talking about. But because the old building had twelve-inch-thick walls, it didnt fall down. Thats redundancy. Modern buildings dont work that way.
Five forty Madison uses brick the same way it uses glass, as a veneer that bears no load. Picture it: a wall 39 stories tall but only one brick thick. What keeps the skinny wall standing is its connection to the frame of the building. But that connection is remarkably tenuous: a strip of corrugated steel one tenth of an inch thick and perhaps eight inches long -- the construction-industry equivalent of those plastic ties that come with jumbo trash bags -- planted in the wall every four square feet of brick. If the contractor skimps on brick ties, all bets are off. Most modern architecture depends, if not on brick ties, then on bolts, or steel angles, little pieces of hardware.
About a month before the bricks began tumbling on Madison Avenue, the Whitney Museum finished reinstalling the 1,500 six-hundred-pound granite slabs that make up its façade. The Whitney, a sleek powerhouse of a building, was a mess behind the granite. Architect Marcel Breuer made one bold statement, but the buildings original contractors apparently built it with whatever metal fasteners they could find: When we took off the skin here, says the projects restoration architect, Diane Kaese of Wiss, Janney, Elstner Associates, we found galvanized steel, we found brass, we found stainless steel, we found regular carbon steel. We found painted steel. We found unpainted steel. You name it, we found it. It was crazy. It was wacko.
The problem that afflicted both the Whitney and 540 Madison -- inadequate or improper anchoring of the façade -- is commonplace. Every structural engineer or restoration architect, it seems, has an anecdote. Some of the scarier stories involve marble, an opulent material that suggests permanence but is actually quite brittle when its sliced an inch or two thin, as it is on many contemporary buildings. In Chicago, the owners of the 82-story Amoco Building waged a decade-long battle to keep the slabs of Carrara marble, weakened by humidity and pollution, from slipping right off the side of the building. Finally, they gave up and re-sheathed the tower in granite. Meanwhile, at the General Motors Building on Fifth Avenue, the owners have instituted an Ongoing Marble Panel Repair Program to secure or replace marble slabs, which, according to building-inspection reports, fall apart on a regular basis.
Marble is not a good material, especially in an atmosphere like New York, where you have high acidity in the air, notes Matthys Levy. It doesnt do that well in Rome, either.