The Checklist Manifesto_ How to Get Things Right - Atul Gawande [25]
What results is remarkable: a succession of day-by-day checks that guide how the building is constructed and ensure that the knowledge of hundreds, perhaps thousands, is put to use in the right place at the right time in the right way.
The construction schedule for the Russia Wharf project was designed to build the complex up in layers, and I could actually see those layers when Bernie Rouillard, Salvia’s lead structural engineer for the project, took me on a tour. I should mention here that I am not too fond of heights. But I put on my hard hat and followed Rouillard—past the signs that said WARNING: CONSTRUCTION PERSONNEL ONLY, around a rusting nest of discarded rebar, over a trail of wood planks that served as a walkway into the building, and then into an orange cage elevator that rattled its way up the side of the skeleton to the fourteenth floor. We stepped out onto a vast, bare, gray slab floor with no walls, just twelve-foot vertical steel columns ringing the outside, a massive rectangular concrete core in the center, and the teeming city surrounding us.
“You can see everything from here,” Rouillard said, beckoning me to join him out on the edge. I crept to within three feet and tried not to dwell on the wind whipping through us or the vertiginous distance to the ground as he good-naturedly pointed out the sites along the waterfront below. I did better when we turned our backs to the city and he showed me the bare metal trusses that had been put into the ceiling to support the floor being built above.
Next, he said, will come the fireproofers.
“You have to fireproof metal?” I asked.
Oh yes, he said. In a fire, the metal can plasticize—lose its stiffness and bend like spaghetti. This was why the World Trade Center buildings collapsed, he said. He walked me down a stairway to the floor below us. Here, I could see, the fireproofing material had been sprayed on, a gypsum-based substance that made the ceiling trusses look gray and woolly.
We went down a couple more floors and he showed me that the “skin” of the building had now been hung at those levels. The tall, shiny glass and steel exterior had been bolted into the concrete floors every few feet. The farther down we went, the more the layers had advanced. One team of subcontractors had put up walls inside the skin. The pipefitters had then put in water and drainage pipes. The tin knockers followed and installed the ventilation ducts. By the time we got down to the lowest floors, the masonry, electrical wiring, plumbing, and even some fixtures like staircase railings were all in place. The whole intricate process was astounding to behold.
On the upper floors, however, I couldn’t help but notice something that didn’t look right, even to my untrained eyes. There had been rain recently and on each of the open floors large amounts of water had pooled in the same place—up against the walls of the inner concrete core. It was as if the floor were tilted inward, like a bowl. I asked Rouillard about this.
“Yeah, the owners saw that and they weren’t too happy,” he said. He explained what he thinks had happened. The immense weight of the concrete core combined with the particular makeup of the soil underneath had probably caused the core to settle sooner than anticipated. Meanwhile, the outer steel frame had not yet been loaded with weight—there were still eighteen stories to be built upon it—and that’s why he believes the floor had begun to tip inward. Once the steel frame was loaded, he fully expected the floor to level out.
The fascinating thing to me wasn’t his explanation. I had no idea what to make of his answer. But here was a situation that hadn’t been anticipated on the construction checklist: the tilting of the upper floors. At a minimum, a water cleanup would be needed and the schedule adjusted for it. That alone could throw the builders’ tidy plans off track. Furthermore, the people involved had to somehow determine whether the tilting indicated a serious construction defect. I was curious to know how they handled