Collapsible formwork for concrete walls

A collapsible formwork element, the element including:

• a pair of opposing side wall panels each formed of extruded polymer material;
• and
• at least one connector member extending between the side wall panels, the at least one connector member formed of extruded polymer material,
• wherein the at least one connector member includes a centre portion between a pair of hinged ends provided by hinge portions in the connector member, wherein the hinged ends are engaged with the side wall panels such that the element is movable between an expanded configuration, wherein the opposing panels are spaced apart, and a collapsed configuration, wherein the opposing panels are relatively closer together, and, on expansion into the expanded configuration, the formwork element is mechanically maintained in the expanded configuration, and
• wherein the hinge portions comprise a material that is more flexible than the material forming the remainder of the connector member, which is substantially rigid, so as to provide a hinge type action.