The use of the compression molding technique to manufacture polymeric panels from recycled polymers was evaluated. polypropylene (PP), polyethylene (PE), and polystyrene (PS) single polymers and their blends were manufactured both with and without UV and flame-retardant additives. The materials were tested in three-point bending, and the incorporation of the additives always produced a decrease of the flexural strength. The results obtained were compared with the properties of commercially available materials. In particular, PP + PE blends showed a promising mechanical performance. For the amount of flame-retardant additive used in this study, none of the compositions analyzed exhibited flame resistance. The balance between loss of mechanical strength due to the increase of the amount of flame retardant additive and lack of flame resistance was obtained by incorporating more flame retardant through a paintinglike procedure. The method proved to be an efficient way to attend the standard for building construction panels.