Abstract: A form tie for joining the sidewalls of a polymeric concrete form comprises a pair of end trusses with an intermediate web truss. Each end truss comprises a pair of vertical struts with interior and exterior pairs of horizontal struts extending therebetween. The width of the web truss corresponds to the desired lateral distance between the interior surfaces of the form sidewalls. Upper and lower rectangular trusses and an intermediate truss are formed within each truss and rigidified by diagonal struts. The exterior struts of each end truss are embedded in the polymeric form of the sidewalls during the molding process with the interior struts of each end truss sealing the mold openings to prevent expansion of the foam from the mold. The interior struts are coplanar with the form sidewalls and serve as a visual gauge that the form and tie have been properly positioned. End ties having a height of one-half of the form sidewall are extended between the sidewalls at the ends of each form.