KPN Dutch Telecom Company | de Jong Gortemaker Algra Architects

The office building for Dutch telecom company KPN is located in Amsterdam Sloterdijk, an area characterized by dull and non-explicit office blocks. The design for the KPN building presents itself as an autonomous, yet dynamic object fitting within the urban fabric. To build a flexibel and sustainable building with optimal daylight has been the main goal from the start of the project. The square plot is bound by the Teleportboulevard with the main entrance on one side and the railway Haarlem-Amsterdam on the other side on which the parking entrance is located. Urban regulations demanded a seven storey building for the entire plot. The height difference in the terrain was used in an optimal way: the parking underneath the building is at level at the adjacing street on the north side, while on the opposite side the ground floor with the main entrance hovers just above the pedestrian level. This results in a grand entrance with elegant steps on the Teleport boulevard. Despite the strict building rules, we were able to design a dynamic and transparent building. Because the building is not only visible from the street but also from the train and the highway A10 it is important that the building responds to multiple scales, in a way that it is not only attractive for pedestrians but also for passing train travelers who see the building in a flash. The building mass follows the building envelope matching the scale of the surrounding buildings, while at the same time large chunks are cut out of the mass. These recesses transform the static autonomous volume into a dynamic ensemble. The horizontal recesses have their origin in the desire of the client to have a mix of offices with a width of 7.20m and 5.40m. By taking this desire literally in the planning process a maximum flexibility of use was created with resulting in an expressive facade at the same time. At street level the building present itself as a large glass volume, with views offered towards the inner courtyard on specific locations. The building was designed in a ring structure around a central patio. Wintergardens with double-height are situated in prominent places to connect the street with inner world of the courtyard. Many glass buildings look dull when you get too close. In this case the facade comes to life for the pedestrian passerby, who can experience the fine detailing in the window profiles, representing the human scale in the large glass surfaces. The building is divided into four quadrants. Each quadrant has its own facilities and can thus be rented independently. All four technical spaces lay within the building volume adjacent to the courtyard. Therefore this building can do without unattractive rooftop units, which are common on top of most office buildings. The structure of the building is particularly efficient, made with precast concrete pi-shaped element for the facades and column-free spans of 16.6m with precast slabs. As a result the building can be flexibly subdivided to the max. Decentralized installations making it easy to use or rent the buildings in parts.