This news was first published in Finnish at the Puuinfo website.
Structural Systems and Construction Methods
The study found that shear walls were the only structural system used in these buildings. This system allows for a high degree of prefabrication, which may explain its popularity. The construction methods used were either volumetric element construction method (3D), or panel construction method (2D), and the study explored the differences between these two construction methods. Of the 55 buildings selected, over 60% were constructed using volumetric elements.
Structural Timber Products Used in Vertical Structures
The use of different structural timber products varied according to the building’s height and the chosen construction method. Timber studs (lightweight timber) was the most commonly used material in shear walls, particularly in lower buildings. The second most common material in vertical structures was CLT (Cross-Laminated Timber), which was especially used in 7- and 8-story buildings. The sample included only one building where all the typical shear walls were made of LVL (laminated veneer lumber). Additionally, the study observed combinations of different timber materials in the structures. In panel construction, timber studs were used significantly more, whereas in volumetric construction, CLT was used almost as much as timber studs in load-bearing vertical structures.
Thicknesses of intermediate floors and walls
The average total thickness of intermediate floors was very similar in both construction methods, as were the walls between apartments. However, significant differences were observed between projects: the thickness of intermediate floors varied by up to 30 cm, and the thickness of walls between apartments varied by up to 10 cm. The study also documented the total and structural thicknesses of the walls across different buildings.
Architectural Features
The study found that elevators and staircases were most often located adjacent to the outer edge of the building. This solution was particularly common in buildings with a narrow and rectangular floor plan. The second most common solution was to place the elevator and staircases in the central part of the building, which was typical of volumetric building construction. Buildings constructed utilizing the panel construction method generally had higher ceiling heights compared to volumetric buildings. Panel construction method allowed for the implementation of wider room spaces compared to volumetric construction, as a significant portion of the construction is done on-site with panel elements.
Suggestions for Further Research
Further research could examine buildings of the same size in the Nordic countries and Central Europe, or investigate projects that utilize different structural systems, such as post-and-beam structures. It would be particularly interesting to explore how the structural solutions, structural timber products, and their thicknesses in buildings constructed elsewhere differ from those in this study.
Link to the study: https://doi.org/10.37457/arf.146875
Authors of the study:
Antti Tuure
Teemu Hirvilammi
Hüseyin Emre Ilgın
Markku Karjalainen
Tampere University
Faculty of Built Environment
Graduate School of Industrial Timber Construction
https://research.tuni.fi/tpr-en/projects/
