The stirrup is made from 100% recycled plastic. Aside from holding reinforcement steel, it internally braces the permanent formwork. Two widgets exist on each stirrup, one to connect the stirrup to the back rail within the form, and another to secure the mesh in order to provide additional internal bracing.
The permanent formwork, which remains in place after concrete has been poured, is composed of a dense PVC sheet which is laminated with extruded polystyrene to add further insulation. The aluminium back rail allows the stirrup widgets to be easily attached.
Like the stirrup, the base is also made from 100% recycled plastic. Different base sections exist for straight, corner, and external sections of the foundation. The base can be laid directly over a damp-proof membrane, offering edge insulation alone, or it may be laid over 25, 50, or 75mm insulation, offering a fully-insulated foundation.