Abstract: A prefabricated collapsible formwork module is assembled at a factory site, including the provision of a pair of sheathing panels which can be made of insulating material, as well as the mounting of the vapor barrier, the filler strips, bearing blocks, and flexible or collapsible connecting elements extending between the panels extending between the panels to retain the panels when they are being erected. The sheathing panels may also have a waterproof membrane applied thereto, and the concrete reinforcement is assembled between the sheathing panels at the factory site. When the formwork module is fully assembled, it is then collapsed, that is, by moving one sheathing panel against the other including collapsing the collapsible connecting elements and sandwiching the concrete reinforcement which is preferably in the form of a grid, and the formwork module can then be stored and transported to a building site.