AKA: Enso, South Lake Union, Seattle, WA

Structure Type: built works - commercial buildings - office buildings; built works - commercial buildings - stores; built works - dwellings - houses - apartment houses

Designers: Callison Architecture, Incorporated (firm); Glumac International, Mechanical Engineers (firm); Sellen Construction Company, Incorporated (firm); Anthony Callison (architect); Richard Glumac (engineer); John Henry Sellen Sr. (building contractor/civil engineer)

Dates: constructed 2009

13 stories, total floor area: 525,049 sq. ft.

2201 Westlake Avenue
South Lake Union, Seattle, WA 98121-2712

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This mixed-use, two-building group overlooked much of Vulcan Real Estate's extensive building campaign in the South Lake Union area, occupying the southwest corner of the intersection of Denny Way and Westlake Avenue. It combined an office tower, retail space and condominiums in one project. Many of the condominiums were envisioned to be used by employees of Amazon.com, which expanded operations nearby in Downtown and in South Lake Union rapidly after 2000.

Building History

The development at 2201 Westlake Avenue had three main components divided into two discrete buildings. It sought to combine office space for the then-booming Seattle market, retail storefronts and a sizeable number of condominium dwelling units.

Vulcan Real Estate announced its intention of building on speculation a mixed-use development at 2201 Westlake Avenue in 11/2006. Building on spec--without tenants lined up before construction started--is always considered risky; Seattle's downtown real estate market was considered a good investment in 2006, due to high employment figures in the region. As originally envisioned, 2201 Westlake was to contain 300,000 square feet of offices, 135 condominiums, and 25,000 square feet of retail space. The condominums were to be located in a 19-story tower, with the office development in a separate 12-story building. It was located across the street of Vulcan's existing mixed-use development at 2200 Westlake Avenue, that opened in 2006.

Twenty-four thousand gross square feet of first floor space was devoted to various retail uses.

Building Notes

According to Glumac, an energy engineering firm that worked on the buildng: "Enso was the first mixed-use, high-rise residential project in the city to earn LEED Gold certification. The two adjacent structures share a single high-performance central energy plant, which moves waste heat and cooling between the office space and adjacent condominium tower according to the time of day, optimizing the efficiency. Daylighting is featured throughout, with the entire façade of both structures covered in glass. All office levels at Enso include underfloor air delivery for efficient heating, cooling and ventilation. Additionally, water efficient fixtures and recycled or renewable materials were used throughout to demonstrate how to bring sustainable concepts to commercial spaces." (See Glumac.com. "Enso (2201 Westlake)," accessed 05/31/2018.)

2201 Westlake occupied 26,754 square feet (0.61 acres) in 2021. It contained 525,049 gross square feet,323,192 net.