Neither from spatial nor geographical point of view, housing and settlement are general concepts. They rather follow the economic, social, cultural and climatic conditions of each region. Therefore the problems , issues and settlement limitations of different income groups have their own unique features and characteristics. The nature, deficiencies and demands of settlement is different based on income of different social classes. It is obvious that each demands its own solution .One of these solutions is flexible housing. Modern building systems make certain types of flexibility possible in designing and as a result they make improvement possible. While common building systems have not been designed for change .Any change in the form of a building will be accompanied with the destruction of all or part of that building. In order to enhance the capacity for change in the buildings , construction should mostly focus on building’s productivity as well as the innovative methods of construction, so that it can create more flexible structures, the elements of which can be easily replaced ,reused or recycled .The previous and current methods of mass-construction lack a reasonable balance between the functional and esthetic aspects . They also lack the capacity for privatization for the residents of the building. Mass-construction can be developed and improved by applying industrial designing approaches . The present research studies prefabrication approach industry and modular in flexible housing. Flexible housing is designed in a way to easily meet the demands of the changes of life and adapt with the conditions. The advantages of such an approach in designing are significant. Such a design has a more capability of being used for a more period of time ,is more adapted with the goal, adapts with the experience and intervention of the user ,has a more economic and ecological perdurability and easily enjoys the advantages of technical innovations. Considering the demands of the users and time limitations, this advantage proposes the modular and pre-made industry. Pre-made housing is considered as an ultra-time and possible attraction for this task. Therefore, it is essential that a planned system acts along the pre-making in order to provide flexibility in housing architecture and prevent it from becoming monotonous. This is modular which provides the possibility of interventions or reductions in flexible housing. Thus the aim of this study made in library and comparative method, is to investigate flexible housing in the contemporary period using modular and premade property. In this way the architect finds an opportunity to produce creative icons with reduction in expense and time and meets the demands for life change of users during their residence . One of the main goals in applying the principles of modular coordinating system is leading the building toward a collection of basic standard scales. Compatibility causes the user to enjoy the same system in various situations .As a result ,numerous systems are replaced with one system .Yet, the functions of compatibility have to be easily applicable by the user. Throughout its life, a compatible system is replaced with a great number of systems. This as a result will lead to saving in money, storeroom space and the charges of installation. Later ,while dealing with housing design, the concepts of flexibility and compatibility are defined .Then by pointing out the advantages of flexibility in housing ,the functional technologies and methods in construction and production with the origin of pre-fabrication and modular are discussed.