The SkyBridge apartment tower is arguably the most interesting high rise residential building constructed in Chicago since the 60s.

What makes it so interesting?

1. What it is not: it is not what Frank Lloyd Wright called a "flat chested building." What did Wright mean by his sexist moniker? When Wright saw Mies van der Rohe's residential highrises at 860-880 North Lake Shore Drive in Chicago, he was disappointed by the fact that they were "merely" post and beam and called them "flat-chested" buildings. Wright observed that Mies was using steel like lumber, much like the original Chicago School did, and was a bit turned off. To Wright, using steel in post and beam construction was evidence of the designer's ignorance of how materials worked. (Wright may have been sexist, but he was NOT a Chicago School Architect. More on this another time.) They're also boxes. By comparison, Wright's proposed residential highrises a block south on Pearson were truly groundbreaking. Allow me to explain why:

Wright embraced the organic which at its simplest means that the structure and that which forms the space are one. Post and beam, or classical architecture as it essence, can be thought of as having separate structural and space-enclosing systems. Thus you have partitions that you can move at will. This is more flexible than what Wright proposed on Pearson Street (where Lucien Lagrange's soulless, overpriced junk is being completed), where you stuck with the walls you had because they were holding up the building. Wright's Prairie Houses are halfway--they have slabs holding up the roof while at the same time employing non-load bearing partitions to divide and create space.

The architect Ralph Johnson of Perkins + Will has designed something akin to a high-rise Prarie House in that he uses shear walls to "break the box." The facade is pulled in and out. The perimeter isn't the flat plane that is customary on high-rises. For instance, many of the apartments have exposure on 3 sides. That's a neat trick. one of the sides may only be 2 feet, but for ventilation and sight lines, it's fantastic. He handles this articulation brilliantly on the east and north elevations. (If you are from Perkins + Will, please tell us more about the design process and the intentions of the design team.) The west elevation is a bit more flat and is a little disappointing.

By comparison, with the exception of other buildings designed by Perkins + Will, all of the other new high rise residential buildings in Chicago are post and beam with a flush perimeter walls. There is little articulation in their curtain or storefront window walls. Johnson has given Chicago something new and special. It is one of the few examples where architectural wisdom has triumphed in Chicago over an impoverished realtor's agenda.

2. It is life at its base: There have been many high-rise buildings erected in Chicago that have little life at their base. They put little thought and effort into expressing what's there. Skybridge has a Dominick's grocery store at its base and an entry at the north end is a wonderful labyrinth that again brings to mind Wright and his five turns to enter a house rule. There's even a reinforced concrete planter. There's a nice set of turns that enliven your entry.

3. There's a long wall of glass along the Halsted Street elevation. In lesser hands it would be monotonous. Johnson uses employs large panes of different colored glass to create a lively pattern.

4. It is essentially two towers after the 13th floor. They are joined by a "SkyBridge" and hence the name of the building. The bridge can only be rigidly attached on one side and must be on rollers so that it will not interfere with the movement of the tower on the other side. This is a neat engineering trick.

5. The large cantilevered overhang at the top of the building carves a spectacular picturesque profile that will definitely make the movies or frame a fashion shoot. The penthouse deck looks like something out of a James Bond movie.

6. Supposedly, the building only cost $7 million (approximately 10%) more than a conventional design. (Perkins + Will itself is owned by investors in the Middle East. So they are obviously making money off of cutting edge design. Who would have thunk it possible?)

7. The one negative is Skybridge's proximity to the expressway, a huge pollution source. To his credit, Johnson proposed a giant garden and building complex to cover the expressway. The facades are sculpted to help break up the stagnate, polluted air. So he has thought about it.

What do you think?

Why do you think Skybridge is remarkable? or not?