Designed and built in one year

The Scandinavian countries in general have a very strong tradition of building with wood, making them one of the world’s leading pioneers in the development of modern timber buildings today. Multi-storey wooden buildings for residential, commercial and cultural purposes are a common feature of local metropolises and towns. Sweden recently impressed the world with the 73-metre high Sara Kulturhus, while Norway has the world’s second tallest wooden building, Mjøstårnet – see our article on the world’s tallest wooden buildings. It is not just about the maximum height, but about the general confidence of investors, municipalities and residents in large wooden buildings.

This is also evidenced by the newly completed six-storey wooden office and commercial building called Lumber 4, designed by Norwegian company Oslotre for developer Skeie Eiendom. It is located in Kristiansand, a city of 80,000 in the south of Norway, whose historic centre consists of traditional wooden houses. The architects and designers from Oslotre Studio proudly continue this building tradition with their modern wooden building.

Oslotre is not just an architectural firm. Given its professional scope and experience, it describes itself as a “design & build consultancy”. Its main representatives have many years of experience in wood processing and its subsequent application in the construction industry. Oslotre is also behind the HasleTre project in Oslo, the world’s first demountable office building. They then applied their knowledge to the Lumber 4 building, which was reflected in record speed – designed and built in just one year.

“Construction of the building was completed in record time, with detailed design and construction taking just 12 months. The Lumber 4 building proved that it is possible to build competitive timber buildings compared to the same technical standards of concrete and steel structures. After completion, the building was 90% leased,” the authors summarise.

The building has a total of 6 floors – the ground floor is used for commercial space to support urban life, while the 5 upper floors are occupied by offices. The floor area of the building is 3890 m2. From the outside, the sculpted façade of prefabricated pine panels of greenish colour, between which a strictly regular grid of fixed windows almost the entire height of the floor is set, is striking. The interior features light wood tones and wood-fibre acoustic panels. In addition to large windows, the atrium over two floors with a staircase made of solid wood brings in plenty of daylight.

The load-bearing structure of the building is deliberately admitted in the interior. The columns and beams are made of glued laminated timber, while the floors are a composite of CLT panels and concrete to meet fire and acoustic parameters. All insulation is made of wood fibre.

According to the authors, the construction costs are comparable to conventional steel and concrete buildings. In addition to significant time savings, the choice of timber construction also resulted in a significant reduction in the building’s carbon footprint – specifically a 53% reduction in carbon dioxide emissions.

Thanks to Oslotre for providing the material.