Abstract: Environmentally friendly, halogen free, expandable graphite (EG) dominant, physical intumescent fire retardant coatings were studied. Comparisons about thermal degradation, flame retardancy and heat insulation between physical EG dominated flame retardant coatings and the traditional chemical (APP/PER/EN) fire retardant coatings were made. Experimental data show that the physical flame retardant coatings possess more advantages over the chemical coatings as to the aging resistance, water resistance and flame retardancy.