In the late eighties, Mercado and González (1991) developed the concept of Habitability, defined as the suitability of the built environment for its residents, focused on residential environments. The evidence suggests that housing habitability is an important aspect of social sustainability, as it affects family's quality of life, social climate and health. In this paper we sought to describe several studies that are supported by the Habitability Model which is considered a way of evaluating residential environments, related to a set of design variables and consequences for the inhabitants. The Model was first developed using Multidimensional Scaling, and later confirmed through Path Analysis. The Model shows a central global measure of habitability and three groups of variables surround it: emotional, symbolic and behavioral. The model seems to explain relationships between architectonic design and residential environmental evaluation through habitability, and family's social processes that are linked to sustainability. Practical and theoretical implications of the results are discussed.