{"id":209885,"date":"2024-09-09T15:07:13","date_gmt":"2024-09-09T19:07:13","guid":{"rendered":"https:\/\/www.constructionspecifier.com\/?p=209885"},"modified":"2024-09-12T16:21:55","modified_gmt":"2024-09-12T20:21:55","slug":"nitro-west-main-seattle-facade-design","status":"publish","type":"post","link":"https:\/\/www.constructionspecifier.com\/nitro-west-main-seattle-facade-design\/","title":{"rendered":"Seattle\u2019s urban transformation: Innovative facade design"},"content":{"rendered":"

By Peter Krech<\/strong><\/p>\n

\"modern<\/a>
Photos by Benjamin Benschneider<\/em><\/figcaption><\/figure>\n

Two projects in the Greater Seattle area with an integrated approach to facade design were recently completed by Graphite Design Group. This approach utilizes a pre-engineered, high-performance curtain wall system as a chassis while employing distinctive, bespoke elements on the exterior that are unique to each project to reinforce underlying design concepts.<\/p>\n

Through close collaboration with the client, contractor, and envelope supplier, a high degree of customization was possible while simultaneously managing cost and ensuring constructability, longevity, and performance.<\/p>\n

Nitro<\/h2>\n

Nitro is comprised of two towers occupying a full city block in Seattle, Wash.\u00a0 The north tower\u2014Nitro North\u2014is 24 stories, with ground floor retail, amenities on levels two to five, with workplace floors above. Nitro South is also anchored by ground-floor retail. Levels two to eight are shared, with a portion of each level occupied by Amazon and a portion occupied by Mary\u2019s Place Family Center. Part of Amazon\u2019s Denny Regrade campus, the project was the fourth block of a campus eventually comprised of nine buildings. The towers are linked by a two-level sky bridge, allowing Amazon employees convenient access to shared spaces between both towers.<\/p>\n

Design concept<\/em><\/h3>\n

The design of the towers sought to emphasize the composition of the two-building ensemble on the block, provide continuity with adjacent Amazon campus buildings, and employ an evocative, dynamic cladding language that shifts in appearance as one moves around and through the block, viewing the building from different vantage points. Just as the sky and surrounding environment reflected in the facade changes throughout the day and seasons, so does the building, presenting a constantly changing pattern language.<\/p>\n

To achieve the expressive cladding language, a pattern of birds in flight\u2014specifically a murmuration of starlings\u2014was abstracted, pixelated, and projected over the entirety of the facades as an underlying organizational element. Seemingly abstract, this pattern changes in rhythm and density as it moves across the surface of the building\u2019s skin.<\/p>\n

Material selection<\/em><\/h3>\n

The curtain wall used is a unitized system like that used in neighboring campus buildings, employing a graphite gray color for the aluminum framing elements and operable windows that blend harmoniously with the glazing. All tower facades are cloaked in this same system to emphasize the shapes of the towers that bend and fold in response to site influences and contextual relationships.<\/p>\n

At the sky bridge linking the towers, full-height clear glass with a custom frit pattern is employed to emphasize the linkage between the structures and provide visibility to the activity within. Translucent, amber-colored glass fins also highlight the bridge, catching sunlight and projecting a subtle color to the interior space.<\/p>\n

\"tall<\/a>
Exterior facade of the Nitro development.<\/figcaption><\/figure>\n

Focal element<\/em><\/h3>\n

While the underlying curtain wall system is largely conventional to match the aesthetic and performance of the balance of the Amazon Regrade campus buildings, the exterior expression is wholly unique.<\/p>\n

The design team worked with Walters & Wolf (W&W) to develop the building envelope, employing three different projecting fin profiles and four different colors (silver and three shades of blue), each of which is interchangeable within the underlying system. The fins may be oriented either left or right on each unitized panel, which themselves can have different fin profiles and colors in the vision and spandrel zones, doubling the number of potential variants.<\/p>\n

The result is a customizable system, with thousands of different panel combinations possible as individual elements are \u201ctuned\u201d within each curtain wall unit.<\/p>\n

The starling pattern was deployed over the facade by mapping a pixelated image of a starling murmuration over the facade and assigning a unique fin depth, color, and orientation to each panel to suit each unique pixel. Graphite Design Group, a Seattle-based architecture firm, worked with GLY and W&W to manage an \u201caddressing\u201d system for each panel to ensure each panel within the wide variety of variants was correctly located on the facade.<\/p>\n

In addition to dynamic fin depths and locations, further visual movement is gained by a deliberate use of color on the fins. The projecting fins on each facade\u2014whose depths range from 102 to 203 mm (4 to 8 in.)\u2014are \u201csided,\u201d using a detail that allows for a two-tone color expression, presenting silver to one side and one of the three shades of blue to the other. From some vantage points, only the silver is visible, but as one moves around the tower and the opposite side of the fin becomes visible, the entire facade shifts subtly from silver to blue. The varying tones of the blue further this sense of movement, adding subtle depth and variety to the facade.<\/p>\n

\"\"<\/a>
Graphic of the systems and details of the facade of the Nitro development.<\/figcaption><\/figure>\n
\"\"<\/a>
Graphic of the exterior facade pattern of the Nitro development. Images courtesy Graphite Design Group<\/em><\/figcaption><\/figure>\n

West Main<\/h2>\n

West Main is a three-tower ensemble, ranging from 16 to 17 stories, occupying a large site in Bellevue, Wash., Seattle\u2019s growing neighboring city. Principally high-tech office use, the site also features ground floor retail, an art program, and a public plaza. Tower one is freestanding, while tower two and tower three are linked at levels one and two by a shared podium.<\/p>\n

Limited in size due to zoning constraints, the towers adopt simple rectilinear footprints above the podium. Each tower employs a variant of an offset core to provide flexible, unobstructed workplace floors. The cores were located where towers overlapped, emphasizing views outward from the site while not compromising access to daylight.<\/p>\n

Design concept<\/em><\/h3>\n

As a multi-tower project, the design sought to emphasize a cohesive relationship between the towers, reflect important aspects of the context and history of the surrounding neighborhood, and provide each tower with a unique identity.<\/p>\n

Early on, it was discovered the project site was once the location of a seasonal streambed\u2014Meydenbauer Creek\u2014which flowed across the site enroute to Lake Washington. This prompted exploring the concept of \u201cflow\u201d both in the site and tower designs. A subtle pattern was mapped across all outward-facing facades, a pattern that ebbs and flows from tower to tower. At podium levels, a similar flow pattern is mapped onto the glass itself, utilizing parametric modeling and digital printing technology to deploy a continuous pattern over individual glass panels on each street-facing facade.<\/p>\n

The tower composition further emphasizes the cohesiveness of the site by utilizing two distinct facade languages that change depending on the relationship to the site. Those facing outward from the site were termed the \u201ccity faces,\u201d while those facing inward, towards the interior of the site, were termed \u201cinside faces.\u201d<\/p>\n

Each tower is further differentiated through exterior curtain wall detailing, each of the towers using a unique vocabulary of fins and projections, each identified by a name: \u201cpush-pull,\u201d \u201cweave,\u201d and \u201ctuft\u201d for towers one, two, and three respectively.<\/p>\n

Lastly, the opaque portions of the offset cores are their own distinct design element. Clad with tens of thousands of individual stainless-steel tiles, the core walls express a colorway unique to each tower, with a pattern that graduates vertically, featuring more saturation at the base of the tower and less at the top.<\/p>\n

Material selection<\/em><\/h3>\n

The tower curtain wall materiality varies depending on location and how it contributes to the overall design concept. Inside faces are a smooth, fully structural sealant glazing (SSG) system and utilize gray-tinted glazing. City faces are highly articulated and receive the \u201cflow\u201d pattern mapping. City faces also uses a more reflective, silver-toned glazing that is common to all three towers.<\/p>\n

Podium glazing is clear to facilitate views into retail and promote visibility of the printed flow pattern. Curtain wall framing is a platinum color common to all towers. The podium curtain wall is graphite gray, and the tower fins are white to emphasize the varying pattern from tower to tower.\u00a0<\/em><\/p>\n

Focal elements<\/em><\/h3>\n

The project gained great economy by employing the same underlying curtain wall system across all three towers. The unitized system provides excellent performance, aesthetics, and flexibility to incorporate operable windows, a specific tenant request.<\/p>\n

As discussed, variation in glazing selection from facade to facade within this system supports the overall design concept. Variation is achieved by using unique custom profiles on the exterior of the system. These vary by tower. Further, differing accent colors at the podium and core wall help make each tower unique:<\/p>\n