Abstract: An intumescent coating system and method therefor is disclosed for thermally protecting a substrate having a surface exposed to a flame environment. The coating system of the present invention is provided as having a having a first component which forms a rigid carbonific char foam having toughness and rigidity, and a second component which forms an insulative carbonific char foam having a density about half the density of the rigid carbonific foam to give insulation properties. The two foam components may be separately provided in a laminate-type arrangement as, respectively, an inner coating layer coated and cured on the surface of the substrate to form an inner film layer, and an outer coating layer coated and cured on the inner film layer to form an outer film layer. Alternatively, the two foams may be provided as being formed from components blended to comprise a single coating layer which is coated and cured on the surface of the substrate to form a film layer.