Two Union Square, Seattle – Architecture, Design and Construction
Two Union Square – Design and Architecture
Two Union Square architectural design captures the regional essence of the Pacific Northwest for the first time in high-rise architecture. From the design and construction of one-acre courtyard at the base of the building to the top of the 56-storey tower, the building reflects the values, natural environment, and economic resources of the region.
Two Union’s greatest contribution to the people of Seattle may be its three-level, one-acre exterior courtyard. Pedestrians can enter the landscaped courtyard at three levels, through a number of interior and exterior walkways. Easy access and covered paths encourage people to stroll through the space at all times of day and during all weather conditions.
As an alternative to the outdoor gathering place of the courtyard, the fireplace lobby on the second floor provides a warm, inviting space for people to relax or meet friends. The focal point is the curving fireplace, with two Honey Onyx mantles, bordered by African olivewood. The warm sand-coloured custom carpet emulates the patterns left by an ebbing tide on a Pacific Northwest beach, similar to the pattern of the blue carpet in the entry vestibule and retail corridors. The carpet is bordered by a wide field of Blue Arden granite.
Two Union Square Building Construction and Technology
This famous architecture has enclosed elevator lobbies which reflect the deep browns and greens of the great Pacific forests. The walls are panelled with Makore wood and Baltic Brown granite; the floors are covered with custom moss green carpet surrounded by Hulean Jade marble. Special details include custom green fused-glass hall buttons filled with a random pattern of air bubbles, and corresponding amber fused-glass light fixtures in the elevator cabs. The 30 elevators transport passengers to their destinations at a speed of 1,600 feet per minute.
The architecture design of tower is basically a crystalline box with applied regular and reverse curved forms capped by a white, sloping penthouse angled towards Elliott Bay. The curvilinear forms of the tower recall sails and ships’ prows, airfoils and jet wings. The white colour and unusual penthouse configuration are light-hearted references to the magnificent snow-capped mountains surrounding the city.
Also Read: Market Place Tower, Seattle’s Design Details
While the tower architectural design is simple in form, its skin has many subtle details. Ochre-coloured vertical and horizontal lines form a “supergrid” on all glass facades, providing scale and relating the tower to the ochre-coloured columns at its base. White curving horizontal spandrels on each face contribute to its slender and elegant proportions, minimising the bulk and width of the building in relation to One Union. The spandrels, some of which are accented by a series of white rectangles, have been broken in places by vertical lines that mark important relationships with surrounding city axes. Each of the tower’s facades exhibit variations of these elements, responding to differences of context and presenting four distinct faces to Seattle’s skyline.
Structural Design and Engineering
Two Union Square has ten column-free comer offices on most floors as a result of the tower’s floor plan and structural design. Traditionally, skyscrapers are constructed and framed in structural steel. Instead, Two Union Square’s centre core, which supports 60 percent of the gravity load and all of the lateral forces, is supported by four ten-foot-diameter hollow steel columns filled with high strength 19,000 psi concrete, the strongest commercial concrete in the world. This central load-bearing capacity allows for minimal structure around the outer walls and in the rental spaces of the building. Rather than exposed cross-bracing or closely spaced exterior columns, Two Union utilises just 14 small composite perimeter columns spaced as much as 46 feet apart.
Using large columns in the centre core freed rental space and increased space-planning efficiency by as much as ten percent. In addition to architectural plans and designs, column-free corner offices provide corridors with unobstructed views in all directions.
Two Union Square Parking
Two Union Square Parking offers tenants and visitors all type of convenience, whereas Weekdays offer Complimentary Valet parking with low evening and weekend rates of $7 are also available.