The project is the result of a design competition for the conversion of an office block into a residential one. The aim is to give new value to the building, re-thinking the internal distribution as well as the re-design of the façades with the use of natural wood for a better thermo-acoustic insulation. The accurate study of the existing typology was the starting point for the concept underlying the project, along with energy-saving and sustainability. In fact, the project works with the mass of the building, for a better sun exposure, proposing, on the one hand, a partial subtraction of the volume and, on the other, developing the new building with a sloping volume, in the south side. The subtracted material has been therefore re-used in the north side, raising the building by two new floors.