Fyrtornet, Malmö | Sweden
11 levels make Fyrtonet Sweden's tallest wooden office building. It was built using 1,640 m³ of binderholz CLT BBS and 1,030 m³ of binderholz glulam. Even the entire staircase and the lift shafts were done in solid timber. Our b_project team led the timber structure's project phase, took care of statics, works planning, pre-fabrication and delivery of all solid wood parts via rail as well as all associated fasteners and even carried out timber installation work.
FACTS
Project Fyrtornet office building, part of the 'Embassy of Sharing'
Location Malmö, Sweden
Completion 2024
Client Granitor Projects AB
Construction company Byggnadsfirman Otto Magnusson AB
Architecture Wingårdhs
Timber construction statics binderholz
Material use 1,640 m³ of binderholz CLT BBS, 1,030 m³ of binderholz glulam
Sweden's tallest office building made of wood
The solid wood project was built in the Hyllie district in the south of Malmö as part of the 'Embassy of Sharing' quarter development for which Granitor Projects AB was responsible. In English, 'Fyrtornet' means 'lighthouse' – a fitting name for this prestige project. The building itself houses a city library, meeting spaces and several office spaces. A red wooden facade, which is typical for Sweden, is used on the outside while exposed spruce dominates the interior. Architecturally connecting the exterior with the interior and hidden behind a second facade, spacious terraces provide space for relaxation and exchange of ideas.
Sustainability, resource preservation and circular economy played a big part in this project. Aside from a glass facade with built-in solar panels, the designers aimed to build the entire structure from solid wood from the outset. This is why, complementing the conventional glued-laminated timber support/beam construction, combined with CLT BBS ceiling elements, both lift shafts and the entire staircase were designed and built from solid CLT BBS. binderholz led the timber structure's project phase, statics, works planning, pre-fabrication and delivery of all solid wood elements as well as all associated fasteners and timber installation.
Challenging timber construction statics and project phase
The statical challenge of this office tower lay in the irregularity of its individual floor plans. The rooms located on the ground floor (café, bakery and bistro), for instance, cover less area than the library above them. Thus, all loads created by the upper levels had to be transferred onto the recessed ground floor. The team not only had to safely transfer vertical loads, but also all horizontal loads through the solid wood construction.
To better analyse the requirements towards the building's wind load reinforcements, a structural analysis of the building based on a wind tunnel test was conducted. These and other findings were used to create the most economical and effective solution to reinforce the building in the form of glued-laminated timber diagonals, some of which span 3 levels and an interior, reinforcing CLT BBS core including lift shafts and staircase.
The challenging timber construction statics and project work as well as works planning were completed by a Binderholz Construction Systems project team over a period of 15 months. The glulam and CLT BBS solid wood elements were produced at the two Austrian binderholz sites in Jenbach and Unternberg. In order to minimise the time needed for assembly, which took seven months, most solid wood element joints were prefabricated.
Delivery of all solid wood elements via rail
Logistics are a central part of the processing of large-scale projects and thus, the binderholz site in Hallein served as the hub for the rail loading of all solid wood elements. Thanks to the use of rail instead of the conventional truck delivery, we were able to save 100 tons of carbon emissions. A major advantage of rail delivery lies in the storage areas that local train stations offer. This way, the delivered material can be temporarily stored in an economical way and the construction site can then be continuously supplied with timber construction parts, ensuring trouble-free assembly.
Apart from expert assembly of solid wood construction elements, much attention was paid to protecting the elements from the weather. To temporarily protect the respective parts of the building, a prefabricated roof was used to cover the lift shafts, stairwell and venitlation ducts. Details on moisture protection and the construction site moisture management plan created by binderholz were constantly reviewed and documented during construction in collaboration with the client. The binderholz moisture management plan protects large-volume and large-area timber construction projects from direct damage as well as follow-up weather damage during construction.
Photos: © Granitor © binderholz
Renderings: © Granitor © Wacker Ingenieure
Plans: © Granitor
