AKA: 1101 2nd Avenue Office Building, Downtown, Seattle, WA; 2nd and Seneca Building, Downtown, Seattle, WA

Structure Type: built works - commercial buildings - banks (buildings); built works - commercial buildings - office buildings

Designers: Mithun, Incorporated (firm); Thiry, Paul, FAIA, Architect (firm); Wright, Howard S., (HSW) Construction Company (firm); Omer Lloydgeorge Mithun (architect); Paul Albert Thiry Sr. (architect); Howard S. Wright (building contractor/developer)

Dates: constructed 1968-1969

4 stories, total floor area: 147,672 sq. ft.

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1101 2nd Avenue
Downtown, Seattle, WA 98101

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Building History

Seattle architect Paul Thiry worked with the Howard S. Wright Construction Company on the erection of this Washington Mutual Savings Bank Headquarters. The building was dedicated on 09/21/1969. A caption for a photo of the new building in the Seattle Times read: “Washington Mutual Savings Bank’s new main office building between First and Second Avenues at Madison Street [sic] is completed and will be dedicated at 2 p.m. today by bank officials and employee [sic], and representatives of the Howard S. Wright Construction Co., general contractor, and Paul Thiry, architect. The $5.5 million structure’s dedication will launch a week-long grand opening celebration tied with the 80th anniversary of the bank. Public events will be held all week, from 10 a.m. to 3 p.m. daily at the four-story headquarters building.” (See untitled photo, Seattle Times, 09/21/1969, p. 4A.)

The building ascended the steep grade on Spring Street, occupying street frontage on the southeast corner of 1st Avenue, along Spring and on the northwest corner of 2nd. The building stood at four stories on 1st, with the first three levels being utilized above ground as a parking floors. (The garage had a total of five subterranean and above-ground floors, with space for 193 vehicles.)

In 2022, the Second and Seneca Office LLC owened this four-story office building.

Building Notes

The Second and Seneca Building had 147,672 gross square feet in 2022, 84,799, net. (The 60,357-square-foot garage being the difference between gross and net space.) It occupied 21,678 square feet (0.50 of an acre) of land.


Owner Rockwood Capital commissioned the Seattle architectural firm of Mithun to supervise the renovation of 1101 2nd Avenue. Mithun collaborated with the firm SGH Structural Engineers to complete the 84,000-square-foot enovation in 2015. Of this renovation, the Mithun.com web site said: "With its slender perimeter colonnade and free-spanning floors, the building presented significant seismic performance challenges. Mithun worked closely with SGH structural engineers to preserve views and large open floors through strategic placement of large concrete shear elements and reliance on carbon fiber reinforcement. The renovation overhauled structural, life safety, skin and mechanical systems while preserving the essence of this successful mid-century design by Paul Thiry, a pioneer of Northwest Modernism. With increased daylight penetration, operable windows, 180-degree views and exposed structure, the building has been transformed from a problem child into a highly desirable urban office space. The original cavernous entry felt unwelcoming and disconnected from the bustling downtown streets. A new two-story glass enclosure captures the prominent street corner, connecting passers-by with activity inside the building and enlivening the urban experience." (See Mithun.com, "Reinventing a Mid-Century Modern Workplace," accessed 10/10/2019.) The effort resulted in LEED Gold certification.