The buildings are part of a larger regeneration plan of the Erzelli hill in Genoa. The Sub4 consists of four underground levels for parking and two office buildings. The office building “A” is ten floors above ground. The two longer sides of the H are rectangular with a maximum size of 57.70 x 17.50m while the connecting part of the building is a trapezium with bases 22.60m and 17.70m and width of 18.60m. The office building “B”, is 15 floors above ground, has a plant area composed of a central part and two offset rectangular blocks. The structures of the underground floors are composite.