Survey of Fire Incidents in Multi-Story Timber Buildings 1996–2023

The study aims to increase knowledge about modern timber construction related to fire by collecting statistics on modern timber buildings, fire incidents, and analysing the data. MSB’s fire incidents for apartments in buildings over two stories in modern timber buildings are compared with fire incidents for all apartment buildings. This is to investigate if the number of fire incidents differs for buildings with timber frames compared to all apartment buildings. Modern timber buildings are defined as those where the majority of the vertical load-bearing parts are made of wood, are more than two stories high, and built after the change Swedish building code in 1994. The definition of apartment buildings includes special housing, such as student housing and care homes. A total of 37,243 apartments built with modern timber construction have been identified. By the end of 2023, there were 3,003,861 apartments in apartment buildings nationwide (SCB, 2025). SCB’s definition includes residential buildings with three or more apartments, including corridor-access houses, and buildings with one or two stories.

All fire incidents in apartment buildings and row, semi-detached, and terraced houses reported by the country’s rescue services to MSB from 1996 to 2023 are included in the study. A total of 93,458 fire incidents for all apartment buildings were reported to MSB during this period. Assuming incidents in the total stock of apartments are equivalent to those in apartment buildings with timber frames, there would statistically have been 354 fire incidents in apartment buildings with timber frames. MSB’s data identified 166 such incidents, indicating a lower occurrence of fire incidents in apartments in timber-framed buildings than in the total population. From 1996 to 2023, seven fire incidents spread beyond the initial fire cell, affecting the entire or parts of the building outside the initial fire cell. This is lower than the statistically expected nine incidents based on the total housing stock. The lower number can be partly explained by the relatively new construction of the studied buildings, but other factors may also play a role.