PortaFab Modular Building Systems | Inplant Modular Office Buildings, Cleanrooms & Wall Partitions portafab, porta-fab, porta fab, modular offices, modular buildings, in-plant offices, inplant, clean rooms, cleanrooms, partitions, prefabricated, enclosures, mezzanines, systems, wall partitions, paint, finishing, curtain walls, architectural panels, formacore, paint booths, guard booths, powder coating For over 25 years PortaFab has been a leading manufacturer of modular building systems. Portafab offers the largest line of modular wall systems in the industry.