One Illinois Center vs Two Illinois Center

Comparing the One Illinois Center and the Two Illinois Center is especially interesting because they share much in common. Both rise in Chicago, IL both were designed by Mies van der Rohe, and they were completed within 2 years of each other.

This overlap gives us a unique opportunity to understand how Mies van der Rohe approached different commissions in the same urban context and historical context during a short period.

The Two Illinois Center is clearly the larger tower of the two, both in terms of height and number of floors. It rises to 374ft (114m) with 32 floors above ground, while the One Illinois Center reaches 361ft (110m) with 30 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.

Both the One Illinois Center and the Two Illinois Center were designed in line with the aesthetic conventions of the International Style style.

The Two Illinois Center was designed at a moment when the International Style style was already in decline, making it more of a lingering expression of the movement. In contrast, the One Illinois Center was built when the style still carried greater cultural weight.

Both the One Illinois Center and the Two Illinois Center were designed to serve as commercial towers, and that has remained their main use since their completion, serving similar roles in the urban fabric.

The One Illinois Center also provides 866 parking spaces.

Both the One Illinois Center and the Two Illinois Center rely on a Frame structural 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.

They also employ the same type of facade, a Curtain Wall facade.

A curtain wall is a non-load-bearing facade hung from the structural frame. It is anchored to floor slabs and transfers only its own weight and wind loads, allowing for sleek, glassy exteriors.