This paper investigates how far social housing transformations have a point of stabilization, whether it affects and how, the use of internal and external private spaces, and residents evaluation concerning the present spatial configuration. Analysis of original plans and of data obtained from two samples of detached houses in IAPI housing estate, and from one sample of detached houses in Vila Farrapos estate, in Porto Alegre, Brazil, was carried out. Data collection was made by means of physical measurements, questionnaires and informal interviews. Social housing transformations might stabilize at a certain point to be considered during its design process.