Although the fire performance characteristics of wood are excellent, fire safety is an important concern in all types of wood construction. In order to evaluate the fire safety of timber constructions, it is necessary to consider the fire performance characteristics of wood in detail. In case of fire, wooden structural members develop a charcoal layer that reduces thermal conduction, combustibility and flame spread, and thus protects the inner part of the cross section.
As, on average, wood burns down at a rate of 0.7 mm per minute, the cross section of the material is reduced by approximately 20 mm in 30 minutes, and by 40 mm in 60 minutes. This is why the load bearing potential of the remaining cross section is of major importance. The respective fire resistance grades F 30 and F 60 refer to the fire endurance of these wooden members. It is interesting to note, after all, that F 30 and F 60 can be obtained without additional flame-retardant treatment. Due to the inherent material properties of this natural building material, the fire-resistance characteristics of wooden structural members are excellent.
As professionals know about the excellent fire behavior of wood, many fire departments are timber constructions.