Panels made of Expanded Polystyrene (EPS) and Ties made of High Density Polyethylene (HDPE) create a Concrete Form that accommodates vertical and horizontal Reinforcing Steel as required. Filling the cavity with concrete creates solid, reinforced concrete walls with 2-4 hour Fire Resistance Ratings (FRR), low maintenance, and outstanding durability. The EPS Forming System stays in place to provide space to run small utilities, serve as backing for finishes, and incorporate superior, continuous insulation layers. The high insulation values, low air infiltration, and high thermal mass can achieve significant energy savings for building owners, operators, and tenants over the building's longer lifetime.