The debate on common spaces inside buildings is linked to twentieth-century forms of popular housing, often devoid of places and opportunities to share a space which is conceived as fragmented and not collective. In recent years, an interest in the appropriation of urban space from the bottom up and the unanimous recognition of the need for places to meet within (or annexed to) buildings, have led to the definition of these ‘intermediate spaces’ as an essential part of living together. Compared to these common spaces, early modern houses pose an essential question: how was proximity within buildings structured, prior to the birth of intimacy? The well-known different perception of promiscuity, in fact, allowed a different structuring of collective housing and a physical proximity that coexisted with the strong social distance sanctioned by inequality by birth. To answer this question, the article examines the types of intermediate spaces, called loci comuni – stairs, landings, passages and courtyards – rather well-known in noble residences, much less in the houses of the popular classes. Through sources such as the fund of the Presidenza delle strade, inventories, land registers, notarial deeds of sale of houses and experts’ estimations, the article will investigate the uses of these spaces made by their inhabitants.