... 4hours. 3,Light Vermiculite fireproof doors are filled with vermiculite senior fire-resistant core as the fire doors core: Its advantages as ... half of the weight of traditional products. 3SmootherThe wood fire-doors with vermiculite, the surface is smoother, not sparkling4easy to ... fire five hours, plus four hours, three hours, two hours, one hour, and so on all levels. 7 fire rated board for fire ...