摘要：Abstract The objective of this research was to acquire a basic knowledge of architectural planning to understand the changeability and long‐term occupancy for dwellings from the survey and analysis of actual occupancy records and conditions of apartment buildings over a long period. The subjects of the survey were households that were long‐term occupants of public rental housing estates that were constructed in the 1960s. The dwellings and records of infill improvements were analyzed along with changes in family structures. In some apartment buildings that were surveyed, an additional living area had been built onto the balcony side, and as a result of having more living space, young couples with children had moved in later. In contrast apartment buildings that had not had any additions were occupied by only elderly households. For households that wished to continue living in the same place for a long term, despite rental housing restrictions, scenarios were observed in which infill improvements had been actively implemented on the inside to improve habitability.
