Mass timber offers natural protection; when exposed to fire Mass Timber burns on the outer layer, called a char layer. This char layers acts as insulator or protector covering from the internal timber that maintains the structural integrity of the building itself during a fire, delaying heating of inner unburned wood layers. In addition, a fire engineering expert will determine the timber sizing in conjunction with fire ratings within the buildings location, as well as the  assembly and sprinkler system design to optimize safety.