Timber as a building material continues to break boundaries and reach new heights, literally.
By Dineo Phoshoko
Gone are the days where high rise buildings are built using conventional building materials. Timber skyscrapers have arrived and are making their mark across the world.
Located in the Finnish city of Seinäjoki, the Periscope tower is a giant wooden periscope structure that serves as an observation tower and engages the viewer in a dialogue with the landscape.
Made entirely of wood, the building is composed of an inner core of cross-laminated timber (CLT) and an external wooden frame that serves as a load bearing structure. The inner core made of CLT forms the frame for an extra-large periscope with stairs circling around it. When taking the stairs up or down one can experience a rich range of different views framed by the various openings cut into the structure.
The tower is composed of three prefabricated elements with the roof forming a fourth element. The façades and the stairs are made of larch. The details and the security netting are of steel. The idea was to create a simple wooden structure of high quality in a way that supports learning and reflects a commitment to empowering and strengthening the local community.
The Periscope Tower is situated on the shore of a man-made lake that has been built on top of a hill in the vicinity of the centre of the city of Seinäjoki. The man-made lake, Lake Kyrösjärvi, has been created in order to serve three main functions: to help keep the flooding in the plains of Ostrobothnia under control, to generate energy for the electric power plant serving the city of Seinäjoki, and to form an attractive site for a new residential area to be constructed on the shores of the lake. 120 000 square meters of new housing will be built there to provide homes for about 2 000 people.
The IBA Woodcube project in Hamburg Germany, demonstrates how the traditional techniques involved in solid wood construction can be re-interpreted in a striking design.
Woodcube, a five-storey apartment building, consists almost entirely of wood; neither glue nor any type of protective coating has been used. Slab-like balconies jut out of the untreated, naturally ageing wooden façade, and are a marked feature of the building’s design. Inside, wood forms just as conspicuous a feature of the building as it does on the outside: ceilings, outer walls, and floors all have wooden surfaces. One utterly novel feature is the bare solid wood casing around the massive staircase, which eschews layering or adhesives. In addition to forming the structure of the building, the 32-centimetre-thick solid wood walls also provide complete insulation.
The Woodcube puts untreated wood, as one of the oldest and most traditional construction materials, at centre stage, but gives it a completely novel spin. Solid wood is an integral part of the whole building and is made as visible as possible in the ceilings, outer walls, and floors. As the façade has been left untreated, it is ageing naturally, emphasising the aesthetic of wood as a building material.
Strandparken Hus B
The Strandparken Hus B is a 540m2 wooden building located in Stockholm, Sweden. The building consists of 31 apartment units and was built with Canadian cedar.
The shingles were mounted under a temporary roof, which made the entire construction site dry and comfortable. As the elements of cross-laminated massive wood are very light compared to concrete, the attic had to be fixed to the foundation with bolts. Shingles were chosen because of their natural variation in colour. Although the façade will turn grey, shingles are able to handle variations in colour naturally and without any demands for maintenance.
The building has gained a wide recognition, and been awarded for their forward-looking, yet traditional and well proved, technology. The architecture has a parallel character; contemporary in its combination of wood, glass and balconies, but also conventional in its almost iconic house shape with references to a widely spread type in Swedish post-war architecture.
The Norwegian town of Brumunddal is home to Mjøstårnet, the tallest timber building in the world. At 85.4m high, the building was opened in March 2019 and holds the record for the world’s tallest timber building.
Mjøstårnet has a combined floor area of around 11 300m². The building has 18 storeys that include apartments, a hotel, offices, a restaurant, a rooftop terrace and common areas. Peaking between 80 and 90m high, the structure boasts intriguing anti-fire features. According to Even Andersen, a fire consultant with Sweco Norge AS, glulam, or glued laminated timber, was used in the construction as glulam beams don’t burn.
The structure was first assembled at the factory in Moelv before being transported to the building site for final assembly. During construction, several hundred glulam beams were hoisted into place in the structure over the course of a 10-month period. The height of the top part of the building of the building – with the pergola beams – was increased by 4.4 metres. To achieve this, the pergola beams at the top had to be rounded off to reduce wind loads. They were initially planned to be rectangular.