One Sansome Street Building vs 101 California Street Building

Comparing the One Sansome Street Building and the 101 California Street Building is interesting because they both stand in San Francisco, CA, and were completed within 2 years of each other, but they were designed by different architects.

This offers a unique glimpse at how rival designers approached projects in the same city during the same era.

The 101 California Street Building is clearly the larger tower of the two, both in terms of height and number of floors. It rises to 600ft (183m) with 48 floors above ground, while the One Sansome Street Building reaches 551ft (168m) with 42 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 Sansome Street Building and the 101 California Street Building were designed in line with the aesthetic conventions of the Postmodernism style.

At the time, this style was at the height of its popularity. So both William L. Pereira and Johnson/Burgee Architects followed what was in many ways expected of them, producing designs that fit comfortably within contemporary architectural norms, rather than breaking with convention.

Both the One Sansome Street Building and the 101 California Street Building 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 two buildings opted for different structural and facade solutions.

The One Sansome Street Building uses a Framed Tube In Tube system, which combines a strong central core with a perimeter tube of columns, while the 101 California Street Building uses a Frame system, that relies on a regular grid of columns and beams to sustain its weight.

And when it came to the facade, the Modular went with a Modular facade, which employs prefabricated panels, often mixing solid surfaces with smaller windows, while the 101 California Street Building opted for a Curtain Wall facade, that uses a lightweight glass curtain wall hung from the structure.