A glass look for Amazon’s urban treehouse at the heart of Seattle

In Seattle’s South Lake Union neighbourhood, one office building follows the next. But these aren't just any offices. This is where the headquarters of online giant Amazon are located. Between modern cafés and restaurants, 40 office buildings rise from the ground. In 2021, the company expanded its headquarters and built more modern glass buildings as part of the “Rufus 2.0” project – including Block 18. This office building was designed in the image of an urban tree house. A wooden staircase winds through the centre of the building, immediately catching the eye from the outside thanks to the glass façade. These glass elements were brought to life using the Ködispace 4SG warm-edge system from H.B. Fuller | KÖMMERLING to meet the high specifications in terms of excellent energy efficiency, durability and ultra-modern design.

There is hardly another inner city in North America that is as dominated by one single company as Seattle. Ten years ago, the Amazon online mail order company moved to the South Lake Union neighbourhood – not far from the eponymous park and lake. Today, the headquarters not only encompass 40 buildings, there are modern cafés, restaurants and food trucks on every corner. An Amazon tram even takes employees and visitors to the very centre of the Amazon headquarters. There, at the heart of the city, one office building follows the next. Names are virtually always written in large block letters on the façades of the Amazon buildings. Sometimes a building is named after Fiona, the first Kindle e-book reader, sometimes after the previous owner of the building, the “Van Vorst” mattress factory.

There is a very special story behind the “Rufus” building. Amazon’s first campus dog was a Welsh Corgi named Rufus. He belonged to Amazon’s former editor-in-chief and chief engineer and would accompany him to the office every day. The four-legged friend was affectionately dubbed “Amazon’s smallest volunteer” and evolved into an unexpectedly productive member of the team. For example, employees let Rufus click the computer mouse with his paw to launch some of the very first Amazon pages. The online giant is still a dog-friendly employer to this day: at the Seattle headquarters, every day is an open day for dogs. Employees can bring their four-legged friends to work, there are special dog parks and it is not unusual to find food and water bowls in the lobby areas of the buildings.

The “Rufus 2.0” project – ultra-modern building complexes in Seattle

Rufus is still an important part of the Amazon story. You can tell by the fact that the online shipping giant gave its modern new building project the name “Rufus 2.0”, which was completed last year. “The Spheres” glass igloos are certainly one of the project’s most spectacular buildings. The three interconnected domes are reminiscent of the Eden greenhouse in Cornwall, a botanical garden in a class of its own. The counterpart in Seattle serves as a lounge and greenhouse and is the new landmark of the emerging metropolis. Large glass fronts were not only used for “The Spheres”, but also for the numerous high-rise buildings on the Amazon site – for example the “Day 1” and “Doppler” glass towers.

Block 18 was also built as part of “Rufus 2.0”. It is a 17-storey building in the Denny Triangle neighbourhood and houses some 36,046 square metres of office space. Block 18 was designed by the Seattle-based Graphite Design Group an architectural firm based on the model of an urban treehouse. One of the main features of the high-rise building is its treehouse staircase. From the outside, it looks as if this wooden staircase, which zigzags up 17 floors, is holding together or connecting the two glass parts of the building. Construction work began in 2018 and the office complex has been completed for a year and a half.

Robust, resilient and durable thanks to warm-edge system

As with many of the ultra-modern buildings on the Amazon campus in Seattle, Block 18 also draws the eye with its spectacular glass façades. To meet the high demands for outstanding energy efficiency, reliable sealing, long-lasting stability of the façade and ultra-modern appearance, the glass elements were realised with the Ködispace 4SG warm-edge system from H.B. Fuller | KÖMMERLING. The reactive thermoplastic spacer for insulating glass ensures the highest energy efficiency and maximum service life. “Insulating glass with Ködispace 4SG has proven to be exceptionally robust, resilient and durable,” explains Dr Christian Scherer, Head of Business Development Glass at H.B. Fuller | KÖMMERLING.

The use of the elastic and reactive Ködispace 4SG thermoplastic spacer creates an edge seal that is flexible and gas-tight over the long term. The chemical bond of the material to both glass and the silicone secondary sealant ensures an extremely stable system. As a result, Ködispace 4SG not only compensates for the loads that occur due to the temperature differences between summer and winter that are common on the American West Coast, it also reliably keeps out moisture and wind. This is especially important in Seattle, where the climate tends to be dry in summer and humid in the other months. The functionality of the glass is permanently maintained thanks to the warm-edge system. This not only ensures a comfortable environment in the offices, but also sustainably reduces heating and air-conditioning costs in the long term.

The space between the panes is virtually invisible

The warm-edge solution also excels in terms of design. The spacer system is applied to the insulating glass fully automatically with an application robot. This enables high-precision production down to the tenth of a millimetre, even with multiple panes – without any of the disruptive offsets experienced with conventional spacer profiles. Ködispace 4SG also prevents unpleasant light reflections. While metal spacers detract from the appearance due to their shiny surface, the matt black Ködispace 4SG reflects the frame colour and makes the space between the panes virtually invisible – for a perfectly unobstructed view.

“Amazon has built its sprawling headquarters in Seattle with more than 40 state-of-the-art buildings. We are pleased to have contributed to giving one of these office complexes the flawless look it deserves with our warm-edge system,” says Dr Christian Scherer.