Hexawood By Coco van Weelden


​By Coco van Weelden (STUDIO44X)



In the Netherlands, one of the smallest countries of the European Union, high density is a big issue. Most of the cities show a popular historic city centre, in which high rise has no place. However, with more and more people drawn towards this low-rise places, housing becomes a major issue.

During the sixties an exception has been made in the city Utrecht. The so-called Neudeflat functioned as a progressive model for renewal, by being the first high rise building in the city. I propose to relive the sixties and expand the existing building by adding additional floors atop. The result will be a model for renewal once again.


The existing structure of the building formed a source of inspiration for the new one. The shape of the building could be divided into triangles of beams and columns, which is structurally efficient since the use of material could be minimized because of the grid that works together in carrying the forces.

The advantages of the structure are numerous. Because of the columns an open floor plan is created for a flexible use. In combination with columns that are placed back from the facade a free view at all sides on the building is created.


The columns are widened at the top in order to reduce the span of the beams and therefore reduce the height of the beams as well. The whole system can be fully prefabricated which adds up to a quick construction process. Central in the building is a CLT core, which contains two fire escape staircases, two elevators, two ventilation shafts and toilets. The dimensions of these elements are minimal and therefore make a compact core in order to have more rentable floor space.


The model of renewal does not end with the structure. As for the climate installations in summer cool air is led into the room on the bottom of the north side of the core, following the earth wind and fire concept. It is then slowly heated up and goes naturally to the south side where it is sucked in by the solar chimney. The sliding doors in the facade can fully open for natural ventilation and night cooling. The horizontal and vertical canopies prevent the sun from entering the space directly. Lastly, there is a strongly ventilated area between the balcony and the facade of the building to prevent a heat bridge.

In winter the opposite occurs. Air is preheated before entering the room. It slowly heats up further before leaving the space. Besides, the trajectory of the sun is shorter in winter; also it stands lower at the horizon. Therefore the sun enters the building and heats up the parafine core wall, which steadily radiates its warmth to its surrounding area.

All these measures rely on natural heating, cooling and ventilation principles. Together with the use of wood for a high rise building the building forms a model for renewal.

City Above the City architecture competition

Plan B : City Above the City architecture competition 

Metsä Wood challenged architects and students around the world to push the boundaries of modern wood building design in the urban environment. Entrants from 40 countries created their Plan B to urbanisation using wood (Kerto® LVL – laminated veneer lumber) as the main material. The task was to design a wooden extension to an existing urban building. The entries were designed to 69 cities worldwide.

Explore the designs