The Cosmopolitan

Seattle, Washington






The Cosmopolitan makes an elegant contribution to the downtown Seattle skyline. The 33-story building includes a rooftop terrace, street-level retail, eight levels of parking, and an amenity level with an exercise room and swimming pool.

One of the most distinctive structural features is the "drophead" around the core. A concrete shear wall core is wrapped by a six foot wide thickened slab on three sides. This allowed the slab to span uninterrupted nearly forty feet from the core to the building perimeter. The drophead provided completely open living units and parking layouts due to elimination of all internal columns.

The Cosmopolitan is a fine example of the economy, efficiency, and flexibility that cast-in-place post-tensioned concrete provides for multi-family construction.


2008 National Award of Excellence
Post-Tensioning Institute

2007 National Finalist Award
National Council of Structural Engineers Associations

2007 Winner, Cast-in-Place Structures
Washington Aggregate and Concrete Association