Abstract—This paper deals with the structural safety and rehabilitation of a 25 year old building of Engineering College at Hyderabad, India. Rehabilitation of structures have become very essential on account of many factors. Deterioration of a structure may occur due to a host of factors such as poor workmanship, improper maintenance, atmospheric effects, abuses, accidents, natural calamities, etc. Certain causes like environmental effects, natural calamities etc, can't be controlled. Damage assessment and structural safety of an old building was studied through non- destructive and destructive tests. In-situ strength of an existing college building was assessed from the design curve developed by the authors without taking cores except for cross verification of results from the same building. The feasibility of extension of floor of an existing building with rehabilitation measures was also studied.