The space between load-bearing walls of the historic popular house in Seville is barely three meters wide, due to the length of the roundwood with which they were used to forge. This unit of measurement offers a recognizable domestic scale that is repeated in the continuous mass of the historical fabric of the city. The small size resulting from the spaces limited by the walls does not allow the rooms and the corridors to coexist in the same space, hence the gallery, the exterior staircase and the patio as traditional communication spaces. The project intervenes in one of these popular houses between party walls measuring 8 x 8 meters, built from three bays perpendicular to the façade and divided into three rooms, one of which is a patio at the back. The house that we found was the product of a refurbishment a few decades ago. This intervention wasted space by introducing a transversal corridor and ignoring the patio. The current intervention proposes hollowing out the entire central space, introducing a staircase that disembarks in the central areas of each bay, reserved for wet areas, and finally reaches the roof, reserving the corners as illuminated and ventilated places through the street and patio. The new central space functions as a large skylight that illuminates the heart of the house in which the metal staircase supported on a stepped base lined with marble recovered from the demolition is inserted. Thus the patio is incorporated into the house by opening onto this central space and a vertical communication arises that does not require corridors to articulate the grid of rooms that make up the house. A second circulatory order around the staircase (on the ground floor through the patio and on the first floor through a small study on the facade that forms a interior window towards the staircase), offers various room combinations that will allow to adapt to the changes in the lives of its inhabitants.