The idea of modernization and reconstruction of the buildings from the socialism epoque is undertaken in many works. Very often however, the subject divides public opinion. Many people are unaware of the architectural potential of those buildings, considering them mainly as evidence of the communistic system. Unfortunately, there is still no protection policy for the modern architectural heritage, which would include objects from the 50s to 80s of the 20th century (monuments protection statute). The article presents the results of the research into the present state of the conservation of selected single family housing types from Polish socialism. The types of housing chosen for the research were realized with the Typical Single Family Residential Catalogue. Projects presented in the catalogue were included into a bank credit program. The types of credits were analyzed by the compliance of the final realization and the original project. The result of the research will attempt to establish the direction of a typical single-family building transformation over the last 20 years. The study will also aim to create the criteria for the evaluation process of modernization such as: technical condition of the building and media, the possibility of adapting a functional scheme to the changing social needs, new building regulations and economics.