In this paper our focus is on smart homes as an emerging phenomenon in care and services offered to senior citizens. The background of this phenomenon is the so-called tide-wave of elderly. Along with socio-economic challenges, politicians express a desire to keep alive the welfare state that offers senior citizen services to maintain their well-being and autonomy. New technologies are therefore considered as a means to meet these challenges. Senior citizens are, like other citizens, a heterogeneous group with different wishes, activities, demands, and expectations rather than a uniform group with similar needs. The boundaries between those included in the smart homes and those not, and the very way these are drawn have ontological implications for the subject and object that emerges out of ongoing activities. We ask what kinds of homes that comes into existence due to the integration of elderly, care staff, alarm providers, alarms, sensor and so on. In addition to these entities other more intangible entities such as policies, technological push, and governance regimes are included. We locate our discussion of smart homes as infrastructures to a relational ontology in which humans and nonhumans are understood not as pre-given but come into existence in intra-actions in ongoing material-discursive practices e.g. smart homes offered to senior citizens. Hence what come into existence is dependent on the entities included, entities that are not innocent but “they are necessary for making meaning” and “have real material-consequences“ (Barad 1996:187). Three vignettes are used in the exploration of the thinking house.