Abstract: Currently, solvent-based fire retardant coating is commonly used as a thermal barrier for construction building during fire hazard. Lack of awareness of the harmful impact of solvent-based fire retardant coating has taken the safety of the people in the building at high risk. Thus, this study was about the water-based fire retardant coating with vermiculite addition as an option to solvent-based fire retardant coating. The formulation contained two different acrylic media and the other three active ingredients which were Ammonium Polyphosphate, Pentaerythritol and Melamine. The significant of vermiculite on the formulation was investigated by thermogravimetric analysis (TGA). The surface morphology of formulations with and without vermiculite was observed using Scanning Electron Microscopy (SEM). The degradation result describes the high significant effect of vermiculite in enhance the formation of high temperature residue and the two acrylic media give same interaction with the other additives which indicate in the thermal degradation behavior.