Anatomy of a Building

Craig Webb, a partner and project designer at Gehry Partners, discusses several of the challenges and the innovative solutions involved in the creation of New York’s Inter­ActiveCorp headquarters. The full story from our June issue can be found here.

On most of our buildings we start with a very cut and dry program analysis of the pieces and do relationship diagrams based on those. Most of our buildings are more complex in program; this is an office building—nine floors of typical office space that need to get subdivided and laid out. Because of that, the process was truncated a bit.

We started with the New York City zoning envelope. When we have tight sites like this, we build a kind of cage that is the outside of the zoning envelope. Anytime we make a model, we had to be able to put the cage over the model. Then we started exploring different ways the façade might articulate. Basically, we wanted to keep as economical of a building as we could possibly build, with the biggest floor plates that would fit in the envelope, in order to conserve as much money as possible to spend on the façade—that’s the trick, right? We made probably 20 or 30 different models very quickly that explored different ideas about how to fit in the zoning envelope.

First there was a box, then there was a parallelogram; they were all very platonic, simple shapes, and then we explored some very curvilinear shapes. Pretty early in the process, we also looked at some that were brick facades, stone facades, stainless steel facades with punched windows through them. We were building three or four models at a time, working as quickly as we could, then we would show them to Barry Diller and Marshall Rhoades [of Georgetown company]. We’d have meetings at pretty short intervals with them and show them models, and they’d go ‘I like that, I don’t like that.’ These happened about once a month.

It became very apparent very quickly that Barry preferred the all-glass buildings we were showing him, as opposed to some of the brick buildings. What was appealing to him was the simplicity of a building with a single material. It was very monolithic, single idea. He liked that idea and we liked that idea also, so we started just focusing on that. We had been exploring a lot of twisted shapes. We’ve worked on a lot of twisted tower ideas—one of them we actually built in Germany, in Hanover, a small, eight-story tower there. We’d been trying to create that kind of shape in glass. In Germany it was stainless steel with punched windows—so that was kind of in play all along. We started looking at curvilinear shapes that way.

Somewhere along the line, Frank and Barry started talking about ships, boats, sailboats, because Barry was in the process of building a sailboat, Frank’s a sailor and has a sailboat down in the marina. The Disney Concert Hall explores a lot of those kinds of shapes. It’s about the curved shape that’s really kind of pulled taut, catching the wind. Those kinds of shapes are really interesting to us, so that started filtering into the process.

We started building models for those shapes, and we arrived at a sketch model pretty similar to where we ended up. And it looked a lot like a sailboat, and then we get to the part of, ‘Ok, now, how do you make that?’ We had built a big glass roof in Berlin, over the atrium of our building on Pritzer Platz, which is a double-curved kind of fish shape, and that glass is triangulated. Basically, if you create triangles, you can cover any shape you want—they always resolve into a flat plane of glass. We knew we could do that, so we started creating computer models that triangulated, which meant you could curve the shape, do whatever you want. It created a very busy pattern though, because of all these diagonals all over the shape.

At some point fairly early, Permasteelisa entered the picture. We’ve worked with Permasteelisa, an Italian fabricator company in Venice, for the last twenty years—they’ve been really incredible engineers. They built the glass tower in Prague, the big fish in Barcelona, the façade on Disney Concert Hall, so we have a long history of them tackling these really complex engineering problems and solving them. The cost was really a prime factor: if we could get rid of the diagonals, the cost was going to drop.

We were doing mock-ups in our plant in Connecticut. They have all these robotics, glass caps that pick pieces of glass up and put them on the assembly line. As we’re watching, the machine would pick up a ten foot long piece of glass, they’d pick it up in the middle and the glass would just sag from it own weight. So we all started looking at that going, ‘Hey, it’s really flexible!’ We wondered: can we cold bend the glass? We’d experienced shaping glass, like in the Conde Nast cafeteria. You make a mold, put the glass in the oven and you slump the glass, but that’s hugely expensive. So now we asked, how about if we just bend the glass on site?

We started experimenting, made two frames of glass, fixed three corners and just started pushing, to see how far it would go in an aluminum frame. We found that we could push the corners of the glass six or eight inches without breaking it. So then we started talking to glass fabricators. The American fabricators just wigged out and said, ‘No way!’ Really the whole issue was whether they would warranty the glass. It’s insulating glass, so it’s a double unit and it has the seals on it. Over time, with the glass bent, it stresses the seals and it would break the seals on the glass, so over time the unit fails.

Then we started doing formal testing, all those things started lining up and we proved out the curved glass. The computer modeling that went on to make the final shape was quite complicated. There were parameters that were set, as far as how much you could bend each piece. The glass couldn’t lean back more than fifteen degrees—if it did it becomes a skylight for the building code. We set up all the rules, then we started manipulating the shape to meet the rules. We went through about three months of very slightly changing the shape to meet all those. The changes that were made at that point were not really that perceptible, three or four inches here, six inches here. Frank was looking at the models and he couldn’t even tell that we were moving it.

We were at many points over budget, which always happens. Originally the back part of the building was curved, then we said: ‘If we make this part a straight vertical flat curtain wall, we can economize.’ Now 30 percent of the backside is just plain old flat curtain wall. The rectilinear part of the building really started to lock the shape into the block. It really attached into the rest of the context and we started to like that. We were really opportunistic – we get forced into something, we really start to like it, we convince ourselves it’s a great idea.”

Categories: Cities