A filtering assembly is laid flat on an outer shroud. An inner drainage layer is set over the filtering assembly while laid flat such that the inner drainage layer overlaps the filtering assembly. The inner drainage layer is sealed and secured to the outer shroud by diffusion bonding or welding while overlaying the filtering assembly. With the filtering assembly held firm between the inner drainage layer and the outer shroud a spiral winding procedure is commenced to roll the flat assembly into a cylindrical shape. The edges are sealed by welding or diffusion bonding. The spiral winding and seam closure can be done on a perforated base pipe or the base pipe can be inserted into the finished assembly at a later time and secured. Alternatively the filtering assembly and outer shroud, with or without the drainage layer can be wound over a perforated base pipe or a complete screen assembly.