The project is born from the desire to study how a semi-detached house, that is to say, with one of its façades completely blind, can achieve natural lighting throughout the perimeter and thus provide the same qualities as an isolated house. To achieve this goal, the strip immediately adjacent to the partition generates a series of triple spaces, skylights and patios that cross all the floors of the house generating a spatial and light complexity as well as crossed visuals both in plan and in section, discovering a surprising interior within a built perimeter resulting from strict ordinances. The programme is organised in a single volume, limited by the minimum distances and buildable depths of the lot. The result is a rectangle located in the middle of the plot, generating an entrance patio at the back and a garden raised in relation to the street, with views of the sea. In the basement, at street level, there is the entrance and parking for two vehicles. At the bottom of the plot, a patio that runs through the entire house, brings light and ventilation to this underground floor. A staircase leads from the entrance directly to the ground floor, where the living room, dining room and kitchen are distributed. Between the living room and the dining room there is a small bathroom that serves this floor and divides the space. The patio contains a closed staircase that leads to the first floor, where there are 3 rooms - two doubles, with a bathroom that jumps over the patio to rest on the partition, and a conjugal room with its own bathroom. A new staircase, arranged immediately above the previous one, goes up to the second floor, where there is a small study that overlooks a terrace open to the south.