A wall form unit for containing a pourable, curable construction material for forming a wall section integrating said wall form unit and said construction material, comprising a first panel and a second panels spaced apart in predetermined relation thereby forming a hollow between first and second panels for defining said wall section and at least one tie assembly having a spacer member for maintaining said first and second panel in predetermined relation, in which both the first panel and second panels are rigid and adapted to retain said construction material, wherein the first panel is constructed of a thermally insulating material and the second panel is constructed of a thermally conducting material. A wall form system for forming a section of wall and wall section and method for constructing same are also defined. The invention also relates to a panel for use in forming a wall form unit and also claims a kit for constructing a wall form unit.