This paper examines the relationship between the inhabitant, the house and the objects it contains to reveal the role that the collection plays in the construction of the domestic space. The focus of the study is the house of John Soane in London, an exemplary case where the collection becomes the defining and creative element of the space. The close connection between collection and architecture is particularly apparent in Descriptions, the text in which Soane describes his own house through the objects in each room, suggesting an imagined tour to uncover the virtues of the architectural space. Soane’s house is consequently shown to be a diverse collection of architecture which takes shape in the simultaneous construction of three collections: fragments of architecture, buildings and constructed architectural spaces. In a way, what Soane creates in the interior of his house is an architectural capriccio, a fantasy that represents an idealized vision of his own “idea of architecture” whose greatest value and attraction lie precisely in the deliberate juxtaposition of the pieces and the dialogue that emerges between them, resulting in a three-dimensional space imbued with intended meanings.