Pittsfield Building vs CNA Center

Comparing the Pittsfield Building and the CNA Center is particularly interesting because they share the same skyline in Chicago, IL, and were both designed by Graham, Anderson, Probst & White. However, they were completed more than 45 years apart.

This offers a unique perspective on how the architect's style and the city's architecture evolved over time.

The CNA Center is clearly the larger tower of the two, both in terms of height and number of floors. It rises to 600ft (183m) with 44 floors above ground, while the Pittsfield Building reaches 551ft (168m) with 38 floors above ground.

Of course, each project may have faced different briefs or regulatory constraints, which we don't really know about and could also explain the outcome.

The Pittsfield Building was designed in the Neogothic style, while the CNA Center reflects the principles of International Style.

Both towers were built when their respective styles were already past their prime. This makes them feel more like late continuations rather than groundbreaking statements, showing how architectural traditions can linger even as tastes shift. The fact that they were built 45 years apart also suggests that architectural fashions often outlast their supposed end dates in practice.

Both the Pittsfield Building and the CNA Center are primarily commercial towers, serving similar roles in the urban fabric.

Originally, the Pittsfield Building was designed for medical, but over time it was converted to commercial. The CNA Center by contrast has maintained its original role.

Both towers share the same structural solution, a Frame system.

A frame structure uses a grid of columns and beams to carry the building's loads. This frees the walls from structural duties, allowing for flexible floor plans and larger windows.

However, when it comes to the facade, both buildings use different approaches. The Pittsfield Building uses a Masonry facade, while the CNA Center uses a Curtain Wall facade.

A Masonry facade like the one seen in the Pittsfield Building features a heavy masonry skin that gives it a more clasical look, while a curtain-wall facade like the one seen in the CNA Center uses a lightweight glass curtain wall hung from the structure.