The composite fabric is suitable as a flame barrier for different articles, such as mattresses, pillows, seats and upholstered furniture and is made from a plurality of joined breathable layers including at least one textile layer and one impervious layer joined including a knitted textile layer made of cellulose fibers of natural renewable origin including at least 50% of cellulose flame-retardant fibers, and the impervious layer including an halogen free plastic material selected among polyurethane or polyester incorporating a known flame-retardant or inhibitor additive.