The house is on the top floor of a building in the historical centre of La Spezia overlooking the bay. The client, a contractor of 35 years, requests that the restructuring work allows for the use of the balcony above the apartment, which is currently accessible by an external spiral staircase. He would also like to get two further bedrooms with two bathrooms and incorporate in the volumetric of the apartment two boxes of iron and glass, a former construction without planning permission which has now been granted.The generated idea was to replace the "vacant space" of the corridor with an entire element that incorporates all the services of the home (storage room, secondary bathroom, changing room, main bathroom), and creates a unique environment between the kitchen, living room and bedroom, expanding the living space to the terrace. The two glass boxes have been recuperated in their original volumetric but integrated in appearance with the façades of the apartment. Both have a prefabricated steel structure that will be buffered later in the yard.Coverage of the box in the kitchen will be unfastened, so as to allow a single glass wall without pillars of support. In both will be used Crystal glass "Heat mirror" PET polymer film with a low solar radiation, to protect the environments from exposure to the south, thus avoiding shielding glass.The connection to the upper terrace will be reinstated with a "cold" internal staircase: a patio with staircase that brings in light to the apartment and works as a solar chimney for ventilation in hot summer days, design choice is also dictated by an economic factor, as it avoids the construction of an external glass box, which can be difficult to obtain approval according to the constraints of building regulations. It also reduces the glass surfaces to a single internal crystal glass surface, which divides the interior of the apartment from the exterior/interior of the patio staircase.