The continuous development of urban centers results in large industrial areas that have been generating large amounts of waste in landfills, as the waste disposal of polyurethane originated in the footwear industry. Furthermore, the growing use of polymeric materials, allied to the various disasters which occur every year involving fires in homes or collective establishments, require the addition of an element that decreases the ability of these materials to act as fuel in materials of construction, furniture, equipments and accessories that constitute different buildings. With this perspective the present work aims to reuse the expanded polyurethane (PU) waste from the footwear industry established in the city of Três Coroas and produce agglomerates with and without the addition of banana fiber (Musa sp.) and cellulose particles (Eucalyptus Grandis), with and without polysulfone (PSf) to perform flammability test. The rigid polyurethane residue was grinded and characterized by particle size analysis (14/28 Tyler mesh, mean diameter of 0.86 mm), the natural fibers with proportion varying between 18 and 26%, were added to increase the mechanical resistance of the final product, and the polysulfone was added in the proportion of 6 to 10% (m / m) as a flame retardant. The agglomerates were produced by mixing a prepolymer based on isocyanate and pressing, and then characterized by flammability test according the norm ISO D3801-10. The results show that the PSF acted satisfactorily as a flame retardant, as only the agglomerate of polyurethane without the addition of fibers and containing polysulfone met the norm requirements, referred as V-2. The addition of fibers only increased and sustained the burning process, however the agglomerates with the addition of banana fiber did not drip, requiring further tests with different concentrations. Keywords: polyurethane waste, natural fibers, civil construction.