The building consists essentially of 4 volumes. Below the surface is a 2-layer basement that covers the entire building plot (approx. 50*50 m2). The basement is primarily intended for parking cars and bicycles. There are also the usual technical facilities, including a sprinkler basin.

The basement is entirely of reinforced concrete and stands on Fundex combination posts with grout injection. Above the ground, the Plinth building fills the plot up to 28 meters above ground level. The lower layers are intended for the entrances to the hotel, the residential functions in the Plinth building and the High Tower.

Project information


Building structures




RRE Blaak Development


UNStudio Amsterdam

Project size

43.500 m2 GFA

Start of project




Consulting services

Structural design, detail drawings and calculation, specifications

The construction of the Plinth building is very hybrid, which means that it is partly comparable to the construction of the two towers and partly more related to a column structure. The floor height from level 2 is 3.1 meters and only fits a residential function.

The Lower Tower reaches 50 meters above ground level and consists mainly of a hotel. This volume extends in 2 directions over the public space, 10 meters towards Blaak and 2 meters towards the East over the Zwartehondstraat. Both projections have left a big mark on the design of the construction. The facades are made of reinforced concrete as well as one of the corridor walls. The walls are of course perforated with openings, but these are determined by the structural possibilities.

The High Tower reaches 107 meters above ground level and goes up to level 33. The floors are flat without beams and bear on walls and columns. The floor is 260 mm thick and completely poured into the work to accommodate pipes in the floor. The walls naturally provide stability.

Characteristic of the Tower is the use of the balconies in the architecture. The balconies are exceptionally long and must give the building a green appearance. The balconies are not connected to a floor as usual as a projection, but are freely laid on the floor edge. The cantilever is provided with a column style between 2 floors located one above the other.

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