Usually the timber itself is encapsulated with several gypsum layers adding a usual fire and charing resistance between 60 and 150 minutes. So that the rooms ar

Usually the timber itself is encapsulated with several gypsum layers adding a usual fire and charing resistance between 60 and 150 minutes. So that the rooms are forming cells in which the fire is contained for a definite time - allowing the safe rescue of people. The jump of fires between floors via the facade is countered by constructional rules e.g. using firewalls (protruding fire diverting metal, wood, concrete bars) or having no burning sequments on the facades. Also node worthy metal and concrete structures have a very unclear burning behavior and do not allow for a safe estimate of the structural integrity. But wood has constant and know charing rate so that an estimate of the structural integrity is far safer and easier to estimate.