© 2015 Taylor & Francis Group, London.Building materials and structures keeping the functionality for many years without any deterioration is called durability. In this study, some experiments such as unit weight, ultrasonic pulse velocity, compressive strength, splitting tensile strength, and surface hardness tests are performed on concrete, partition wall brick and stone samples taken from a 50-year-old structure. Also in this study, the performance loss due to aging of this structure is determined and some superficial ideas are obtained about the quality of structures in the 1950s. Concrete samples are taken from a 50-year-old industrial R.C. building (Yasin-Cakir Flour Factory) and the average compressive strength is 8MPa. Carbonation depth is at a dangerous level determined by phenolphthalein. Changes on the samples show that a R.C. building getting older, becomes unsafe and also the construction technology and used materials were not sufficient and off grade in the 1950s.