Transfer of heat through solid materials driven by a temperature difference. When a fire occurs in one place, the produced heat can be transferred to another place by mean of conduction through solid materials connecting the two sites. Fire can then be initiated at the second place. Other fire propagation modes are Convection and Radiation. Conduction is especially important in conductive material like steel, because when a supporting steel structure is heated to approximately 450oC, it collapses See: Fire Consequences