The double wall consists of two parallel prefabricated concrete skins with a minimum thickness of 5 cm that are joined together with lattice girders. The concrete skins already contain static reinforcement. Double walls are prefabricated off-site in the factory, delivered to the construction site, installed and finally poured to form a solid wall. This results in a cured monolithic total cross section. The advantage of the double wall is the elimination of formwork on site - with a considerably shorter construction time and two fair faces.