Seattle's Rainier Square Tower Tops Out


Just 10 months after the project began, the 850-foot-tall Rainier Square Tower in Seattle has reportedly topped out, thanks to its radical composite steel framing system, otherwise known as “speed core.”

About the Project

Although work on the project officially began in October 2017, it wouldn’t be until early January 2018 that designs for the $370 million Rainier Square Tower were released with experts claiming that the Seattle-based tower would prove to be a "game-changer" for seismic and wind resistance in building structures.

Additionally, the composite structural steel frame—which includes a shear-wall core made up of cross-tied steel-plate walls filled with concrete—was expected to take 40% less time than a more traditional design.

The application, developed by structural engineer Ron Klemencic, chairman and CEO of Magnusson Klemencic Associates, is the first of its kind for a building of such height, aiming for an earthquake-resistant core.

When studies surrounding the Coupled Composite Steel Plate Shear Walls system are complete, the American Institute of Steel Construction estimates that the system will be rated with an R Factor of R=8.

By May, a three-person peer-review panel approved the core system design, giving the innovation the green light from a design standpoint.

“This is going to be a watershed in terms of high-rise construction,” said Shannon Testa, senior project manager for general contractor Lease Crutcher Lewis.

Also in May, however, work was halted by internet juggernaut Amazon when the council announced it was considering a “head tax”—an employee-hours tax on businesses grossing at least $20 million per year in the city. This would raise an estimated $75 million annually, and the council wanted to use the money for low-income housing and helping its homeless population, which is reportedly among the largest in the nation.

The tax was slated to cost Amazon about $20 million per year for the intended occupancy of 722,000 feet of office space in the Rainier tower, and two other tower projects that were currently employing about 8,000 workers.

Further stalling of the project arose when the International Union of Operating Engineers Local 302 hosted a 17-day strike and picket in August.

By February of this year, Amazon announced that it would be withdrawing its occupancy.

Most recently, in August, Rainier Square Tower officially became Seattle’s second-tallest skyscraper in the city when its height surpassed 772 feet.

The Design

Encompassing 1.7 million square feet, the Rainier Square Tower includes a mix of ground-floor retail, underground parking, office space and 200 of the highest luxury apartments in the city. The development will also have an adjacent 12-story, 150-room hotel.

Designed by NBBJ, a global architecture firm based in Seattle, the tower reveals an inverse reflection of the curved base of the Rainier Tower next door, having a wide base instead that curves after the fourth floor, creating a narrow angle as it climbs upward.

The exterior of the building is covered in a nonstructural curtain wall that was designed, assembled and installed by Walters & Wolf, in collaboration with 3Diligent. Together, the companies produced 140 3D-printed aluminum nodes of varying dimensions for the tower’s cladding.

What’s Happening Now

As forecasted, the Erection Co. topped out Seattle’s Rainier Square Tower in only 10 months’ time, after installing the last core model on Aug. 9. In reaching the milestone, the tower officially ranks as the seventh-tallest building on the west coast.

Klemencic reports MKA has five other speed-core buildings on the boards in three projects in California. According to Andy Bench, project manager for the developer, Wright Runstad & Co., the mixed-use tower will be substantially completed by Aug. 13, 2020.


Tagged categories: Architecture; Color + Design; Commercial / Architectural; Commercial Buildings; Commercial Construction; Commercial contractors; Condominiums/High-Rise Residential; Construction; Maintenance + Renovation; NA; North America; Ongoing projects; Project Management; Projects - Commercial; Residential; Residential Construction

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