The fire performance of wood products is very often the limiting factor for an increased application of timber in most countries. To avoid or minimize the flammability the wood is treated with flame retardant coatings. The nature and the size of the flame retardants as well as their distribution within the coatings influence the efficiency of flame retardancy. The aim of the present work is the development of flame retardant coatings for wood applications based on non-halogenated flame-retardant systems by incorporation of inorganic nano-fillers in aqueous polymer dispersions with the result of reduced ignitability and heat release rate. Based on that idea inorganic nano-fillers of different sizes were incorporated into several polymer matrices and the influence of varied processing parameters was investigated by evaluation of filler dispersion using SEM combined with EDX and measurements of properties related to the fire performance such as heat release rate, limited oxygen index and duration of afterglow and afterflame as well as flaming droplets and debris. TGA was used for evaluation of thermal decomposition and mass loss focused on gas evolution relating to the oxygen content. Acknowledgement: The work was funded within the7th Framework Programme under the Grant agreement no: 315425 [WOOD-FLARETCOAT].