Tac Linen production unit has prefabricated r.c. columns that carry the prefabricated roof beams. Those prefabricated roof beams are connected to each other by means of omega shaped prestressed prefabricated purlins. The building covers an area of 29.000m² and also a sub-story of 3560m². The structure has been checked according to the new seismic code of Turkey and as a result the system has been reinforced in steel using special techniques which did not interrupt the production inside.