Abstract: An insulating concrete form foam block bi-directional system comprises a pair of opposed and parallel foam sidewall panels spaced using a plurality of plastic and metal band ties that act as a fire-break between the two exterior finished concrete wall surfaces. Each tie comprises nearly full sidewall height, plastic flanges which engage the sidewalls and a metal band cross-connecting vertical holders of the ties. The metal band forms a wide opening to enhance concrete flow. The tie results in a minimal downward stress impact on the tie during concrete placement. The top and bottom surfaces of each sidewall are formed with raised areas and non-raised areas which interlock with adjacent blocks. The side surfaces of each sidewall are formed with vertical tongues and grooves which interlock with like tongues and grooves of corner pieces which are adapted to form right or left-hand corners.