20 Aug 2023

Fire brigade finds fires in modular timber apartment buildings spread quicker and are more time consuming to extinguish


Fires in tall modular timber apartment buildings can increase the risk of structural collapse, take longer time to extinguish and fires can spread much more quickly than in concrete buildings.  

For the fire departments faced with fires in these types of new modular timber constructions, the fire behaviour of the buildings can present new challenges, according to a news report by SVT.se on August 19.

What allegedly started as an attic fire, ended up spreading downward within the construction of the wooden apartment building in Malmö, Sweden.

The open flames were brought under control by the firefighters in about three hours. However, the five-story building is a modular house where the framework, walls, and roof are constructed with wood. While this construction method is more environmentally friendly, it can complicate firefighting efforts.

"On-site, we experienced that the fire, which originated in the attic, spread through the joints between the modules, and the fire extended as far down as the third floor," says Henrik Greiff, Operational Chief of the Southern Swedish Fire Brigade, to Swedish Television.

It took a total of 50 hours to extinguish the fire in the building. The fire department is accustomed to extinguishing house fires with a significant amount of wood in the structure, but multi-story buildings pose a new challenge.

"It's a difficult and time-consuming task, and we constantly have to assess our own safety within the building," says Henrik Greiff.

He believes ember fires had spread and weakened the structure. The attic and the top two floors were completely destroyed. The fires were enclosed within the walls, roof, and floor, making them much harder to locate.

The entire wooden structure can also be weakened by smouldering in load-bearing components.

"We have encountered this kind of construction before on a few occasions, and it has become more common to build this way. What's new for us is the size of these buildings," says Henrik Greiff.


Photo Credit: 

Ascent MKE under construction, showing its mass timber construction. (Photo not in relation to fire referred to in this article. 

Date: October 31,  2021

Author SidewalkMD

Creative Commons License